Definition: In this task, you are given a Reddit post as a text. Your task is to generate a title for this text. The title should start with "TIFU by", followed by a situation that caused humor. The title should contain 7-12 words, ideally.
Input: Text: this happened today, about 4 hours ago. i'll try to explain the terms i use, but you can just read the tl;dr.  
my friend was complaining about bad battery life on his nexus 5, and i told him that's probably because he never considered a factory reset after updating it. still, my nexus 7 loves to do weird stuff that can easily be fixed by clearing the cache. it's painless and quick. i told him that i can do it and he trusted me - maybe because of my phone dual booting different roms and my linux laptop. i enter recovery mode and there it is - "wipe cache partition". i select it and confirm.... and it's stuck. it should take 2 seconds, not 2 minutes so i rebooted the phone and it entered a bootloop (a soft brick when the phone only gets to the boot animation). i go into recovery and it can't mount /cache... this is bad. really bad. the only way i could repair it was to do a factory reset and he didn't back anything up... and even this might not be enough. with my phone/tablet i'd just use google's factory images (you can use them to replace any partition of a nexus to the factory state) to repair the partition, but he's got a locked bootloader. unlocking it means full wipe. i knew i fucked up. he got mad at me, took the phone and went to the nearest repair shop. i don't blame him for not trusting me anymore. the moment he walked out i started to google why did this happen? i found out it's \\\\**wizard talk ahead**\\\ because of his updates - basically, android's runtime changed between 4.4 and 5.0 - and when i wiped one of the cache partitions there was a conflict with the old runtime's remains in the second partition. when you do a factory reset 3 things are wiped - your /data with the exception of /data/media (your apps), /cache and the dalvik cache - i only wiped /cache. normally it's just not a full wipe, but in this case the two caches were too different to work. \\\\**wizard talk end**\\\ he came back and the first thing that i said was that i'll pay him back with 50% extra. but they wiped the phone and he had no backups... he lost 2 years of photos that he really didn't want to lose. and it's because of me. it works now because it's pretty hard to kill a nexus, but the data won't come back.  
at least the battery drain is fixed.

TIFU by trying to help my friend with his phone.