Why does the iphone repair man need the passcode to my phone?

I need my screen replaced because it is cracked. The repair man says he needs my password to "check that everything is working". I'm not trying to give anyone my passcode because I don't trus anyone! And I have loads of personal information there that I don't intend on deleting. Wtf does he need my passcode for anyway. Can't he just see that it is working just by swiping through the screen to unlock the phone and tapping on the number pad?

He wants to make sure its working when you select different areas, etc. If you don't want him to see it then tell him you will go there and he can it while you are there.

Don't give him it although he just wants it to make sure parts of the screen aren't damaged