Dont buy a coin just because it is cheap. that is not a sufficient reason to buy a coin.
An expensive coin might be a better coin to buy instead of a cheap coin.
A coin worth buying must have the following characteristics
1. A decent market capitalisation that tends to increase either monthly , quarterly or bi annually.
2. A very high trading volume.
3.A decent amount of buy orders or buy support.
4. If it is a cheap coin then that would be an added advantage.