In simpler terms: Water always moves to where the "stuff" (solutes like salt or sugar) is. Water tries to dilute the concentrated side until both sides are balanced.
High concentrations of sugar create an environment with very low water potential. Bacteria or fungi that land on the fruit lose their water via osmosis and die, preventing spoilage. osmosis for plants
Osmosis = nature’s zero-electricity water pump. In simpler terms: Water always moves to where