[gsora]

MicroSD are notorious for being unreliable, especially cheap ones. What MicroSD are you using?

[manmal]

Use a good one, then. I haven’t spotted any issues after 18 months of use.

[gsora]

I explicitly asked for the model/maker of your microSD so that I could :-)

[manmal]

Mine is a SanDisk Extreme PRO 512 GB. But you could get e.g. one of the "High Endurance" ones if you are concerned about that.

To add more context, I only use TimeMachine for the use case "I deleted something I haven't committed to Git and want to revert to the state of 1h ago". My real backup is offsite + encrypted (Arq + paid GDrive).

[msh]

Generally go for ones sold as for "industrial" use.