If Bitcoin price pumps from $1300 to $3000 in few hours, nobody would make profit from it, because the exchanges wouldn't allow you to sell your Bitcoins and make the fast profit, it would bring a big loss for exchange sites.
Do you agree with this?
then how do you know the bitcoin price in the pump if the exchanger doesn't allow to sell bitcoin. I think if you sell bitcoin when at the pump $3000 the loss is who people buy bitcoin at that price so why exchange site must loss if there's pump. (buy and sell not just sell)
Yep . I agree with you also if a reputable trading exchange doesn't permitted traders to sell their site will lpse its reputation .In both sides they will not have a big loss with it because in every buys and sell they have a commission and they only follow on price . In my own opinion only .