potential energy comes from the buildup of pressure or stress. lets say,
for example, that a rubber band is being stretched and then kept at its
max stretching point. at this point if it is to be let go, it would fly
off. why? because of its potential energy turning into kinetic. the
stress of the rubber band being stretched gives it the potential energy
to turn into kinetic, therefore causing it to fly off. i hope this helps
:)