HODLING is the strategy for winners.

No seriously, I'd say it really depends of how much BTC you have and your objectives. Personally I'm not putting all my money into BTC so that I can still live, buy a house, have a car, travel, etc., so BTC is a long term investment. Once my stash is worth enough fiat to buy an island and retire or something like that, I won't have any hesitation and will sell everything (or almost everything).