I never understood altcoin trading. Why would someone bought xmr 3 weeks ago. It is the same thing as buying a lottery ticket. You just buy altcoins and wait for them to get pumped. What if they get dumped and die? It's pure gambling.
it is a bit off-topic here but let me try to explain.
that is the difference between traders and this is the exact reason why you can see at least a dozen topics asking is trading == gambling!
you don't just go around buy random altcoins and hope for a rise, you look around, do some research see what is happening and then buy a potential.
in case of monero, it has always been one of the good coins which is old and could survive this long, it actually offers something that can be useful so it is not a random coin saying we are good.
then you see in the news a lot of talk about monero, dark market, the potential of it to become a currency used in those areas and also check the exchanges to see the volume being high and also growing.
these with a lot of other analysis can help you find such potentials and make your investment.
The sudden rise of Monero was due to Darknet markets suddenly accepting it aside to Bitcoin. I remember when the announcement was first made, price went up a lot.
So it might be a good idea to also follow news from them, in case they decide to add support for other more privacy oriented coins.
Or if there are new markets dealing exclusively in Monero.