I think,in bank our money is safe because many authorities are behind which have expertise to handle the money. No doubt ,banks use our money and they invest that money in stocks and bonds which are risky and from our money they buy assets by which they get benefits but now is time ,we have to understand the the whole concept about the money and bank and how banks use our money and how they double and triple our money by investment in assets and how they get benefits from our money? Every person should learn books and they should be habitual of reading books because this habit will give them excel in life.
The bank knows very well how to use every money of its customers in several things that can make them profit because it is very impossible for the bank to just keep the money of the customers without using it at all. Because apart from the bank who has to pay each of its own employees, the bank owner also really wants to increase his wealth through other important assets in this world so the bank will never stay silent by saving money but they will always move to make money multiply through their own customer funds.
For now, some people have certainly realized that the money they save in the bank will be used by the bank for their interests and in this case, of course, the bank will benefit more than their customers, but for those who have understood this, of course, they will not save their money in large amounts in the bank and of course they will prefer to manage their own money, such as investing in real assets that also have benefits from it.
What you said is very true, the bank must of course pay each of their employees from the profits they earn from the turnover of money in their bank and in this case the profits earned by their customers are very small compared to the profits earned by the bank, therefore if we want to make a profit from the funds we have then we must be able to manage the money ourselves according to the skills we have, because without the right skills it will of course be very risky in managing the funds we have.