You don't need to be in many projects. You just need a few good project and you're good.
Thats what i also recommended but most of the time people invest with random altcoin for more profit and thus they get scammed. On the other hand, old altcoins with potentiality, scam very rarely comparing to new altcoin. But there were lots of new altcoins, those were already given incredibly returns but Newbies are advised to get apart from doing such things.
honestly investing in many projects is okay, the thing is that, many are just randomly picking some random project based on their guts and put their money there.
of course they would definitely get scammed eventually one day.
had they followed only project that is being sponsored by some big company like binance they'd be fine, they could be investing thousand times in a month and their investment will mostly still retains their value even though sometimes the value is going down.
thats simply the key here that many seem to just ignore, just stick with project sponsored by big company.