I have experienced that situation. There's no problem if your coin pump after sell cause that time you will be still in profit but if it dumper after buy, it makes the situation awkward. And I found that, most of the time the coin get dumped rather than pump. Crypto pump randomly when its time of bull season. Right now Bitcoin is very expensive. But i think there's no problem in buying Bitcoin along with good altcoins if you want. If you dont buy, how could you profit then? And in my opinion, crypto will be more expensive soon cause bull season is yet to start
One don't need to invest in some shitcoins to get some good profits, because most time the shitcoins may endup moving in an opposite direction (dumping) so instead profiting the individual will only endup making losses , so we have to be careful on how we use our hard earn funds when it comes to investment.
And investing in Bitcoin only one can Also make some good profit from despite being expensive and all that , that's the reason we have DCA strategy to buy different quantities of Bitcoin, in a fixed time either weekly or monthly. Though it may take time as an average Man to build a good Bitcoin stash , but at the end it all worth it .
Because Bitcoin is a coin with the potential of growth, though there's no guarantees but still worth risking it (investing in Bitcoin), than risking your cash in some risky shitcoins.