Why do some people invest their savings in the stock rather than saving in a bank?

If you keep money in the savings account in a bank, your money will lose value over time. This is because the interest rate provided by the bank is lower than the inflation rate. Your money is losing value although the amount of money is increasing. This is because you would have been able to buy more things at the time which you invested than what it becomes as the price of things increases at a higher rate.

This is why letting your money remain in a savings account is not a good idea, and many people choose to invest their money elsewhere as a hedge against inflation.

Now regarding the people investing in stocks, they may seek a higher return or they believe that they are smart enough to multiply their money through stocks, and that's why they invest in them. It is considered risky, but the reward is also high if you succeed.