Good point, I am in fact nothing compared whoever celebrity you might think of. In my case though the idea would be of some family member or friend unlocking any device (say for something like looking for a picture together or whatever file they might need) and casually stumbling on something I didn't want share. I want to have that kind of control where if I shared something with someone it's because I wanted to, everything else nobody knows about should stay that way. I mean, it's not like I'm hiding nuke codes or bigtiddygothgf.jpg but still, if I didn't tell you then you shouldn't know.
Lastly, yeah I'm dead so it's not my problem but people will remember me for a little while more so might as well think of that too.