If a coin is traded on many exchanges, then it is liquid, and you can invest in it more safely.
Everyone wants to invest in coins that have good liquidity. But when a coin is known and everywhere it is being traded it is usually very expensive. I prefer to invest in early and little-known projects. Then higher chances to earn!
When you buy a token that is not very popular, the risk is much higher that you can not earn anything in the end, but on the other hand its good that you have a chance to sell for a good price during growth