For RPi the two major causes of issues (in my experience) are low spec power supplies and low spec SD-cards.

Power supplies drop voltage when the loads gets too high, which is especially pronounced with high power USB devices like external harddrives.

SD-cards tend to get worn out or give write errors after enough writes. Class 10 SD cards are recommended for both speed and longevity. And ideally try to avoid write intensive stuff on the SD card