Commitment bias is the tendency to be consistent with what we have already done or said we will do in the past, particularly if this is public.
Inconsistency is not a desirable trait, thus people try hard to keep their promises and reflect consistency. Pre-commitment devices can be used to stave off procrastination and temptation in order to achieve goals. For example, if someone publicly commit to their intentions (like going to the gym three times a week) so they become more likely to follow through on their plans.
Market researchers may experience commitment bias when research participants refuse to contradict themselves and stubbornly stick to their initial opinions.