Activities disappear into THIN air, apparently, as do photos

I just LOVE how routes just disappear from Strava!!! NOT, so freaking annoying, man! After I got home where I have Wifi, I clicked finish, selected the pics and "save activity". Today I went to see how many miles I did yesterday, because I did 2 different rides with an activity in between, and that segment is NO WHERE to be found. 1st world problems, I know, but I hate having to take the time to manually input.

This is not a first for me, either. Also, other times, I'll select like 80 pics, I see them all in the app, then when the activity updates, there are like 2 pics that are saved...what gives? I'm quite certain I can't be the only one having these issues? I'd love to know how these SNAFU's can be avoided, if anyone has figured out how to remedy these issues!  Thanks!!