Common Mistakes, Barriers, and Group Decisions
Common Decision Making Mistakes
- Being too dependent on “expert” information.
- Overconfidence.
- Underestimating information from others.
- Filtering data: choosing only information that suits the decider.
- Hearing and seeing only what we want.
- Ignoring intuition.
Barriers to Effective Decision Making
Psychological biases
- Illusion of control.
- Framing effects.
- Discount the future.
Time pressures
Speed-trap thinking; cutting quality for speed.
Social realities
Decisions are political; managers must consider many parties.
Group Decision Making
Advantages:
- More information available.
- Multiple perspectives.
- Intellectual stimulation through discussion.
Risks:
- Groups often inferior to the best individual.
- Conflict and politics.
- Time consumption.
Decision making goes wrong in recognisable ways. Decision makers fall into specific mistakes. Particular barriers stand in the way of good decisions. Group decision making has its own pattern of advantages and pitfalls. Knowing these failure modes is the first step to avoiding them.
Six common mistakes
The handout lists common mistakes that decision makers fall into.
Being too dependent on expert information
Some people rely too much on the experts when in fact not all of them are truly experts. Try widening the search and sources.
A school head facing a difficult decision may defer to an “expert” without questioning the expertise. The consultant brought in to advise on curriculum may not know the school’s context. The textbook supplier’s recommendation serves her own sales targets, not the school’s needs. The “education expert” speaking at a conference may have left the classroom decades ago.
The mitigation is to widen the search. Consult multiple sources. Talk to people inside the school who deal with the issue daily. Treat expertise as one input, not the answer.
Overconfidence
Humbles the overconfident attitude and remain open to possible options.
A decider who is too sure of herself stops considering alternatives. She decides quickly and ignores evidence that suggests she might be wrong.
The mitigation is humility (covered in the Level 5 chapter). A reflective decider asks “what if I am wrong about this?” The question opens space for evidence that might change her mind.
Underestimating information from others
Devaluing information fed by others is a big mistake. A little respect for receiving unsolicited and volunteered information or suggestions is healthy in the decision making process.
A school head may dismiss input from junior teachers, students, parents, or support staff. The dismissed sources often have information she lacks. The peon may know about the staffroom conflict before the deputy head does. The receptionist may know which parents are unhappy before the complaints reach the principal.
The mitigation is to ask widely and listen. The information from unexpected sources is often the most useful.
Filtering data
When filtering information, you only choose those that are in your favour, which makes you biased on a certain decision, making you miss out on other details that can be helpful in the process. Be open to ideas.
Filtering is a form of confirmation bias. The decider selects information that supports her preferred option and ignores information that does not. The decision proceeds as if the filtered-out information did not exist.
The mitigation is to actively seek disconfirming evidence. Before deciding, ask: what would make me change my mind? Look for that evidence.
Hearing and seeing only what we want
Each individual has preferences or biases which gravitate them to certain information. Best way to deal with this issue is to identify your biases and preferences and to be open to the information when making the decision.
This is closely related to filtering but operates at the perceptual level. The decider does not even notice the information that contradicts her preferences. She is not consciously filtering; she literally does not see what does not fit her expectations.
The mitigation is harder than for active filtering. The decider has to deliberately seek out the contradicting view: ask a contrarian colleague, read an opposing argument, run a “red team” exercise where someone argues against the decision.
Ignoring intuition
On many occasions we are actually aware at a subconscious level of the correct course of action. Unfortunately, we often tend to ignore our intuition. Intuition is useful in non-standard situations and in expedient decision making.
Intuition is often dismissed as unreliable. The handout names a real cost of dismissing it: experienced decision makers have absorbed many patterns through experience, and intuition is partly the signal of those patterns.
The skill is using intuition without being captured by it. Use intuition as a check: “the data say A, but my gut says B; what is the gut noticing that the data are missing?” Sometimes the gut is right; sometimes it is bias. The questioning is the work.
Barriers to effective decision making
The handout names three categories of barrier.
Psychological biases
Three specific biases beyond the ones covered earlier.
Illusion of control
People’s beliefs that they can influence events, even when they have no control over what will happen. Such overconfidence in business may be tragic. Decision makers ignore risks and fail to objectively evaluate the odds of success.
A school head may believe she can control variables that are actually outside her control. She decides as if her effort alone will produce the outcome, ignoring external factors like government policy changes, economic shifts, or demographic trends.
Framing effects
Decision bias influenced by how the problem or decisions alternative is phrased or presented. For example, course A had 70% chance of profit and course B 30% chance of loss; the choices were equivalent. Manager selected course A.
The example is from Bateman and Zeithaml. Two options that are mathematically identical (70 percent chance of profit; 30 percent chance of loss) get different reactions because of how they are framed. The first sounds positive; the second sounds negative.
A school head should rewrite her decisions in different framings before committing. “We will succeed with 70 percent probability” vs “We will fail with 30 percent probability” should produce the same decision. If they do not, framing is biasing the choice.
Discount the future
A bias giving short-term costs and benefits more weightage than longer-term costs and benefits. For example, many people would avoid going for dental check-up now even though the condition may worsen in future.
Future costs are discounted relative to present ones, often too heavily. A school postpones essential maintenance because the cost is now and the consequence is later. Then a roof collapses.
The mitigation is to make future costs concrete in present terms. Not “we should fix this someday” but “if we do not fix this in 2026, the cost in 2027 will be triple”.
Time pressures
Today’s fast business setting asks for acting quickly; slow decisions may become irrelevant. But fast decisions may ignore caution, suppress conflict and make decisions on one’s own without consulting others. Managers cut quality. Speed-trap is dangerous.
Time pressure is real but often overstated. A school head who decides everything urgently produces worse decisions. The mitigation is to distinguish what genuinely needs speed from what feels urgent but can actually wait.
Social realities
Many decisions are made by a group rather than by an individual manager. In slow-moving firms, interpersonal factors decrease decision-making effectiveness. Even the manager acting alone is accountable to the boss and to others and must consider the preferences and reactions of many people. Important managerial decisions are marked by conflict among interested parties. Therefore, many decisions are the result of intensive social interactions, bargaining and politicking.
Decisions are political. A school head’s decisions affect parents, board members, staff, students, and government. Each has preferences. Even the “best” decision technically may not be the best decision politically.
This is uncomfortable but real. A school head who pretends decisions are purely rational misses the political dimension and produces decisions that are technically right and politically infeasible.
Group decision making
Group decisions have their own pattern of strengths and weaknesses worth covering in their own right.
Why use a group
If enough time is available, groups usually make higher quality decisions than most individuals acting on their own.
Three reasons:
- More information. Multiple people bring multiple pieces of knowledge.
- Multiple perspectives. Different angles surface considerations one person would miss.
- Intellectual stimulation. Discussion produces better thinking than solo deliberation.
The limit
However, groups often are inferior to the best individual. (Hill, 1982)
If one person in the group is significantly more capable than the others, the group’s decision will often be worse than that person’s solo decision. The group dynamic dilutes her contribution.
The mitigation is to weight contributions, not to give equal voice to everyone. The most knowledgeable person on a topic should have more influence on that topic, even in a group setting.
Common errors in groups
Beyond the individual mistakes covered earlier, groups produce specific errors:
- Groupthink. The group converges on a decision without rigorous testing because dissent feels uncomfortable.
- Diffusion of responsibility. No one feels accountable for the decision; everyone thinks someone else will catch the mistake.
- Dominant voices. The most senior or loudest person’s view drives the decision regardless of merit.
- False consensus. People go along because they think everyone agrees, when actually most have private doubts.
A school head running group decision making should be alert to these patterns. The best protection is to invite explicit dissent (“what does the case against this decision look like?”) and to weight expertise (“on this issue, who in the room knows most?”).
The framing effect is when how a problem is phrased influences the decision, even when the underlying choice is mathematically identical.
The classic example: “Option A has a 70 percent chance of profit” sounds more attractive than “Option A has a 30 percent chance of loss”, even though they describe the same outcome.
The mitigation is to deliberately rewrite the decision in different framings before committing. If the choice changes based on framing, framing is biasing the decision and the decider needs to step back and reconsider on the underlying merits.
Other psychological biases worth knowing: illusion of control (believing you can influence things outside your control) and discount the future (under-weighting future costs and benefits).
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