[villagetinker]

I just helped a neighbor when their garage door (MVP opener) would start to close, and then reverse and stay open. It was intermittent for a few weeks, then would not close. We found the connection of the wires from the sensor to the cable going to the opener to be corroded and loose. Once these were cleaned and CRIMP lug connectors installed the opener works as it is supposed to.
It appears the connections were bad, and when the garage door started to close the vibrations were enough to cause the connections to fail and that causes the door to go to the open position.
I have come across bad connections several times as the original installers typically just twist the wires and tape them up, then humidity (etc) causes the copper to oxidize and the connection fails.

[NoMoSno]

Yep.
I put No-Ox-It on all connections.