I helped my 18 year old son learn that he needs to look at total coins outstanding to help determine how high a coin's market cap might go. He invested in Tron (TRX) and quickly saw huis investment go up %X. He was excited and told me that it would go much higher similar to Etherium (ETH) and Litecoin (LTC). I laughed and asked him how many coins were outstanding for TRX and he said "What do you mean?".
I showed him online how to lookup TRX's total and circulating supply of coins. TRX has Total Supply of 100,000,000,000 and of that over 65,000,000,000 are in circulation. I then had him look up ETH and LTC. ETH and LTC had less than $100 million for each. His eyes went wide and he said "damn!")
He still thinks Tron will go up some more in the long run (a few bucks), but at least I was able to temper his expectations and he took some of his earnings on TRX and moved it into etherium. Since then TRX has gone down 40% and ETH had 10% plus rise.
Look at the Total Supply and Circulation before chasing a hot coin.