Of course the first pair of glasses will weak with the time passing. Some people can have good eyesight but some can't because there are many factors that can affect our eyesight. If we often play computer games, we may have bad eyesight few months later. If we don't pay attention to the eye hygiene in our daily lives, we may get an eye infection and affect our vision too. But vision problems caused by infections will go away on its own after we treat with the infection. In all, our eyesight will drop when we get older, so the first pair of glasses will become weak and useless.