Moral dilemma :
You inharit a task from your team expert (big ego there) he estimated this before sprint as hard 10 days (with overtime).
You have finished it in a very relaxed 4 days (I agree a lot of code was written but that's life).
Now there is the dillma :
If you declare it done by this time you are the rockstar but you getting a very influencing enemy you made him look like a fool...
If you wait do a psaudo work for the remaining time . It's just laying.. And there is 50% your cover will be blown....

What would you do?

Estimates are not only for coding. You have some free time. Use it

Why do you think it'll make him look like a fool? Estimates are *really* hard things to get right. If you've done it in 4 days, good on you! It certainly doesn't make someone who estimated 10 days a fool however. I've got time estimates more wrong than a factor of 2 before.

Only non-tech people think the expert did something wrong.

Who said he'll write the exact same code like you? Maybe the quality of his code might be way better than yours.

As a lead developer, I can tell you I am not really faster than any of my juniors, when it comes to results. But unlike their code, mine implements all features, is future-proof, includes tests, documentation, best practices. It won't need hundreds of revisions until it's considered stable.

Of course I also have a junior which tried to brag in front of the boss.

So I ripped the whole thing appart. Not by power, but by know-how.

From experience: talk to him and let him know you finished it, and ask him to review it. If all good you can deliver to QA and you hit two birds with one stone. Saved yourself from a possible conflict with the senior and also saved your company dev time. Win win.

I actually had two senior devs put 2 different estimates on one task. This happens a lot .

Also, for example, our company includes code review and bug fixes in the estimates, so he probably added some time as a buffer. Don't know your situation.

His definition of "Done" may be different to yours.

Best case is be honest, if you decide to wait 10 days then you had better be damn certain you're Done otherwise you're the one who will come out looking bad