Reason for a crash? [solved, motor/Esc issue]

I have been flying this quad regularly for some time. However, in one of the test flights, it came crashing to the ground. Can anyone help me troubleshoot the reason for the same and how to mitigate that?
Please find the tlog and bin file in the link below.
2022_02_12_S25G - Google Drive

The battery is going from 14 volts all the way down to 11 volts.
The voltage after that is also a little higher than 13 volts.
I believe this battery is a 4 cell.
I think the voltage on the battery power supply low should be higher than 13 volts.

the conclusion is correct, it started to oscillate as the PID’s were too aggressive for such low performance that remained.

It looks like battery voltage sagged from a large current spike concurrent with Motor Output 2 commanded to max indicating a loss of thrust. I don’t think the battery is the root cause.

You don’t have motor thrust scaling configured. Not a cause of the problem but it should be configured.

What was this craft doing that caused this pitch and roll oscillation?

Thank you for your replies folks. The craft was configured to fly in an infinite loop of a rectangle on a small ground hence there is a lot of roll and pitch observed. Also, loss in thrust could be because of the motor/ESC failure. Is there a way to know which of these components gave up?

Not really. Having ESC telemetry can help deduce what happened.

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We use FETtec OneWire 4in1 ESCs. They do not require DMA, and only need three wire connection to the ArduPilot. And are not limited to 6 outputs, you can use up-to 12 ESCs using a single UART port.