Having the person who will be responsible for performing a specific activity estimate the duration for that activity from that person and that may be introduced by having one person estimate the duration for all of the activities.

Generates a commitment, avoids any bias  

Explanation:

Commitment is a promise that shows the dedication towards a person, organization, etc. In the commitment, there is the involvement of the belief, willingness and the cause of the promise of commitment. The people who are committed to the organization or show truly that it is important.

We all should sustain our commitment. Commitment does not happen at a single time. It happened during the period and take time to build. Commitment grows with people when people work together. People make a decision and solve the conflict together.

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