Inflation/Risk
Unfortunately, saving money is not free of risk :(
Inflation is something that occurs in almost every country on earth. With inflation, you generally mean the increase in the price of goods and services in a country (or area) over a specific amount of time (usually one year). In industrialized countries, the inflation today is often quite low (around 2 % / year). But in some developing countries, the inflation may be much higher.
If the inflation is stable at e.g. 2 % / year, this implies that if a certain article costs $100, the same article costs $100 * 1,02 = $102 one year later. Two years later this article costs $100 * 1.02 * 1.02 = $104.04, three years later it costs $100 * 1.02 * 1.02 * 1.02 = $106.12, and so on. This means that the value of money is decreasing, which of course is bad for you.
If you want your money to grow more than a few percent per year you probably have to buy stocks or some other risky assets. If you do so, you can gain much money, but there is also a risk that you lose some money.