When there is water above a water source, other water sources adjacent to the water source flow outwards

When water (source or non source) is above a water source, the water sources adjacent to the lower water source flow outwards instead of staying put. This could cause annoying water flow that pulls players around in player made structures, ocean monuments, ruins, shipwrecks, flooded caves, cave buffet worlds, and waterfalls.

This same glitch applies to lava, but it is way less annoying for gameplay.