I work for an apartment complex as a Senior Maintenance Supervisor and i'm pretty damn good at fixing most things but the answer to this repair is alluding me and my boss doesn't agree with my prognosis. We have a dryer in a residents apartment that would only start occasionally allegedly over the course of about 3 weeks going over there she would stay it wont start i would arrive and start the machine and it would start instantly and without it having problems i could not diagnose it.

I finally got called over there and it would not start i went ahead and swapped her dryer with one from our models and put the defunct one In our model so i could work on it in peace.

I checked all limit and thermal fuses i did notice during the teardown and testing of components that thermal fuse on blower housing was not secured properly on one side so i resecured and the pseudo wool gasket that the dryer has on its lower side to reduce noise during spin and been bungled up

i then put the dryer back together after all that to see if that had made a difference it started so i shut it off to button it up the rest of the way and then tried to start it again with no success it sounded like the motor tried and then nothing. i then began to spin the drum to see if it was hung up clockwise the machine then began to tumble clockwise instead of the counter clockwise i let it run for about 1min without the element on to see what would happen i then shut it off and tryed starting it again it ran, i let it run for about 5min then shut it of and repeated this about 5 times with success i was happy with it working i had lubed up the motor during teardown and had attributed it to the problem i then come in the next morning and am told that the dryer will not start again.. so i ask you the community

tl/dr
Any idea what's wrong i told my boss i believe that the motor is going out because it would only start after me manually rotating the drum and hes a firm believe that if it was going out or dead that it would be locked up and not running at all.. Could a winding in the motor be going bad and how would i test it if its the case?