There are several reasons for that and the most common are bounty participants, because they know that within the first half a year price will likely go down, so they are dumping at the beginning to earn at least something.
not only bounty participants my friend
but early investors too, because a lot of project give a huge bonus to their early investors, especially for private sale investors
for now, a lot of bounty tokens locked in some period time, but a lot of project still down in price after listed on exchange buddy
That is true, bounty campaigns sending tokens few months after the end of bounty campaign with lock-in period. So how can bounty hunters cause a dump?
The team is responsible for the dumps! Their behavior, progress and so on.