Its really easily to fall into the pattern of buying high and selling low and hard to break out of it. If you don't buy based on hype and HODL if things go bad you should be ok. I invest I go in planning to HODL for a year or two this way I dont feel so bad if it goes down right after I buy it and if it goes up then great I can sell early. $100 is a great amount to buy, I only buy so much because I'm using money from past investments so I didn't really work for the money.