One of the things that keep people from trading is the slow turnaround of cash.
If one trades away their coin at the high and the low takes place before the funds are replaced to the checking account, buying back has to wait. Waiting is not an option in this fast moving market, so hodling is the only safe option.
Holding cash becomes as important as holding coin at this point.
I believe this is the reason many chose to hold.
Agreed. But with some, people have gdax or gemini where they can get cash instantly. True hodlers these days have balls of steel.