It can be hard to time the bottom, so if you're thinking that you want to buy a coin, it might be better to just jump in and wait the time it takes for it to rise. If it's a good investment with a solid base, solid team, and a product that is already making money, it should bounce back eventually. Don't miss out on good investments just because you were afraid of paying a little too much.
(Just my opinion, not investment advice)