Until I began shooting Glocks, I never had a problem with a magazine spring. Now I do. Why Glocks have this problem, how extensive it is, and whether Glock is still supplying springs with a relatively short life I do not know.
At any rate, on the minus side, the magazine spring seems to be the weak point in the otherwise strong Glock system. On the plus side, the Glock service department has been very good about replacing problem springs for me at no charge.