[jrockway]

I think that's a symptom of buying off-the-shelf NFC hardware. They all lock you out after some small number of incorrect attempts to guess the password, because some security researcher noticed how easy it was to try every password and people stopped buying their stuff if they didn't have this feature.

This equipment is not necessary for a toothbrush "minutes used" counter, but unfortunately, there is no off-the-shelf alternative.