Why your plans run long

• Most of us guess too low when we plan. Researchers call this the planning fallacy.
• In one study, students guessed they would finish their thesis in about 34 days. On average it took about 56. Only about 3 in 10 finished by their own guess.
• Why? We picture the plan going well. We forget how our last few projects really went.
• The fix is to look back first. Ask, "How long did the last one like this take me?" Start from that number.
• An AI assistant can split a task into steps and guess the time for each. It doesn't know your week. Check its guesses against your own past.