This may be a device fault (loose wires, failing control panel, etc.) but it may be an actual power problem.
In the olden days, a short power outage - even a minute or two - made little difference to anything. Your AC-line powered clocks (whether in an oven or on the wall) would be a minute off and everything else would be "as it was before".
Now many devices, including ovens, have electronics that keep their state only if the power stays on continuously. This includes digital clocks (except the old "flip clocks"), computers, TVs and many, many other devices. They have "soft switches" that don't truly turn the AC power on/off, so that a circuit is running all the time that "knows" whether the device should appear to be on or off. Typically, a power outage of more than a second will turn all of these devices "off", so that when power returns they come back to a default state - typically "appear off" but in some cases "appear on" (e.g., many computers have a setting to automatically turn on after power is restored - crucial for servers, security systems, etc.) and in some cases give a power failure indication (like my Kitchenaid oven).
The big problem is on outages between roughly 1/60 of a second and 1 second. Almost any device can tolerate an outage of 1/60 of a second - one AC cycle. But handling more than that depends on the power supply design. Some devices will ride through several cycles quite easily. Some devices will not. I see this occasionally with failing battery backups (UPS). A UPS is typically designed to switch over to battery power in 1/60 of a second and for any low voltage (perhaps < 100V), not just a full outage. But if the battery has failed then the connected devices get nothing at all until power is restored, and can actually end up worse off than if they simply tried to ride through the outage on their own, particularly if the problem is low voltage rather than a full outage.
End result: If your incoming utility power has some very brief interruptions, you can easily find some devices resetting while other devices act as if nothing ever happened.