The most important thing I’ve learned about estimation is that, especially in larger/more established companies, it really only matters in two basic scenarios:
- Order of magnitude differences - hard deadlines (like a public event you are supporting)
Usually estimations between two things don’t matter as much as prioritizing those two things. Work on the thing that matters the most. If it takes 2 days or 5 days, in most cases it won’t matter - it’s still what you would work on, so functionally estimation wasn’t needed.
If it is a difference of 2 days vs 2 weeks (or some meaningful magnitude to you) then you start having opportunity cost that factors into prioritizing.
Estimation is more often used as a tool for “control and prediction” - how many times have you had incredible success because you controlled or predicted an outcome?