Water left pooled inside maytag neptune front loading washer

Possible explanation: Some water is left in the hose going up to the drainpipe b/c the pump can only pump water with water, not air... so when the last bit of water is sucked up, it 'stays' just the other side of the pump exit nozzle and keeps the drain tubefilled. This water gradually leaks thru the drain exit valve and back into the machine, sometimes siphoning standing water in the drain trap with it.

The valve is either electric solenoid or plastic/rubber clapper in a cylinder. Your call whether to fix or not depending on ease and cost. Probably a $20.00 part.

Cheers!