Not going to generalize this but I have noticed that most of the times when you see someone who actually is buying various shitcoins (something I can never call investment) and they probably have been losing money more and they still stick around this same strategy of buying they are people not making mistakes in my opinion but rather people who are actually trying to get rich quick by buying the next pump coin. Sometimes it is hard to actually hard to get this mindset off from them.
We have infinite number of Alts (sh*t coins) available and irony is that people keep on investing in these coins with mindset that they will go up one day and they never. There are sh*t coins available who has price close to zero and you can buy thousands of such coins in just one dollar. It's about understanding the fact that there is no thing which is fully decentralised like bitcoin and alts have very short span of life.
There are theories like one must have a diversify portfolio but in Bitcoin world there is only one and only coin for investment i.e., Bitcoin. If you are thinking of investing then bitcoin must be your first and foremost choice for investment. Don't think that these Alts can move and behave like Bitcoin.