Here's why:

* Osmosis is the movement of water across a semipermeable membrane from an area of high water concentration to an area of low water concentration.

* Solutes are substances dissolved in a solvent (like water).

* When the concentration of solutes is higher outside the cell, it means there's less free water available outside the cell compared to inside the cell.

* To balance out the concentration, water moves from the area of higher concentration (inside the cell) to the area of lower concentration (outside the cell) through the cell membrane.

This process is essential for maintaining the balance of fluids and solutes within cells.