A lot of depends on potential of the coin and how useful it is.
Cryptocurrency is very volatile. It is good for trading.
But for long term investment coin must be useful.
It is necessary to evaluate the future potential of the coin.
Now there is a big demand in nature protection, that is why the project that protects the planet from pollution like this
https://twitter.com/liquidearth_nft/status/1502269439785541633 has a good potential for investment.
You will have the maximum profit only if you will start to invest during the fall of the market.
But many people invest in cryptocurrency during rise of the market, because when market rise cryptocurrency is very popular.