What reasons prompted the Europeans to look for new sea routes to India?

In the 15th century, the main sea route from Europe to India was under the control of the Portuguese fleet, which is why most of the cargo had to be delivered with significant losses, which went to pay the fee.

Due to the fact that in Europe the demand for spices, silk and other products has significantly increased, and they were constantly in short supply, goods from Asia have risen in price.

In order to satisfy the demand of the population and get a large profit, expeditions were started, which were aimed at finding new sea routes bypassing Portugal.