bitcoin price changes mostly because of events, for example we had halving last year as the biggest thing and this year the Japan news which keeps coming out.
the fact that similar events happened at similar times doesn't mean they will continue to do so.
for example we have the scaling debate still going on and it may come to a conclusion finally and with this UASF thing, price can go wild for a while. and that is going to be new.
Sometimes, changes in Bitcoin's price are due to no reason at all.
People expected the decision on ETF to have a big impact on the price. It didn't. The price just kept increasing although the ETF was rejected. Similarly, although there is no headway on the blocksize discussion, the price has still increased.
technically there is always a reason, the reason may simply be "more people selling than buying"!
and as i said it is always based on events. the rejection of ETF was a big event and it already had its effect the first time, and the second time nobody cared anymore!
and regarding blocksize debate we have already seen one big dip during the $1200 rally the first time.
although i should add that these things can never push bitcoin out of its general course which is rising in long term. they will always have short term effects.