The best I've read so far (but didn't observe myself yet) was, that people dump at the end of the month because… Well, it's the end of the month. And at the beginning of the month… Opposite.
Very good point, and a legit one.People need to pay rents, debts, etc. at the end of the months, so the last days are usually dump days.
Hmm, to be more specific, at least where I live, it is more like the beginning of the month, when payments are due, but your employer hasn't paid you yet, stuff like that. So I would expect prices to decrease well into at least the first few work days of the new month. But as I said, I don't have the means, time and data to prove that this is a legit thing.
Another pattern you can see is big miners dumping their coins on a daily/regular basis, always around the same time. But this is very specific to certain coins and even there not necessarily a pattern you see all the time.
