Deadlines vs. Estimates

The basic difference is this:

• Deadlines come from external sources, for example, “Feature X needs to be ready for the summer trade show”.
• Estimates come from internal sources, for example, “Feature X will take me N weeks to complete”.

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If the deadline is shorter than the estimate however, then that’s when the problems start. Here’s a few hints to help ease this situation:

1. Hint for managers: Let the person doing the work create the estimate
2. Hint for managers: Don’t override an estimate with a deadline
3. Hint for developers: Respect for your estimates only flows from accurate estimates
4. Hint for developers: Accurate estimates come from tiny tasks
5. Hint for developers: Review your estimates after the event
6. Hint for marketing: Explain the reason for the deadline