My estimates are a lot closer than they used to be, but the surprises still get me. I plan for the work I can see, and then the hidden stuff and the creeping scope blow my number apart. I'm better than I was and I still end up explaining why it took longer.
More people experience this than they realize.
Your estimates are better, but hidden work and growing scope still blow them up.
If this sounds familiar, the Library can help you find the bigger picture.