But at some point people will think they are worth more and prices will rise.
Buying shares of fundamentally sound companies when the price is low is how one makes money.
But a stock price doesn't go low, it matches what most people think is the future profit making prospects of the company. So yes you can get a lower price but you're buying shares in a less valuable company so you're not getting ahead. If a stock price seems low to you, you are probably not seeing something that others in the market do. The main way stock investments pay off is buying into a company that has a convincing case for improving fundamentals in the future. Buying "cheap" stocks based on the what the price was last week is not how it's done. People who use their grocery shopping skills to buy stocks usually get burned.