One of the things that ended fuedalism was santitation because when peole filled up their buckets full of pee and poop they would throw the tihngs inside them outside the window and yell "GARDYLOO!" Also, no one even bothered to pick up the poop on the ground so that led to people getting sick.
The Black PLague also know as the Black Death was one of the majotr things that had ahuge impact in feudalism. This horrible disease eneded up wipping out have 1/3 of the population of Europe. That meant that serfs were free to leave the lands of the lords and seek for higher wages.
Many serf were asking for higher wages since many were dying so the Nobles and Kings were now paying the serfs or peasants more money. Also, the peasants working conditions were horrible.
Many wars was also one of the reasons feudalism ended. Also, Many feudal lords died and Kings reclaimed thei land and power.
They could become tenant farmers with all that money and just pretty much be wealthier. It also ended because they rised with the money in the feudal systdm