That depends on where you live. Here a 10 year deposit gives at most 2% interest, and that is at a totally unknown foreign bank. The first big local bank gives 1.2% only for 10 years, which happens to be exactly the same percentage as you pay on tax on savings. So your money doesn't grow at all, and inflation (caused by the massive quantitative easing) eats through it. In 10 years you can easily lose 20 to 40% of its value.