What I noticed that made me suspect the SD card may be failing on RPI:
- sometimes would not boot
2)when it did boot, it took a long time.
3)Using balenaEtcher (previously Etcher), when I created a new img on the SD card, on a successful boot I began to see that there were things that existed that should not have existed on a fresh install.
4)Gparted was not able to delete the partitions.
This was my first SD card failure, and I got educated! LOL