The HODL strategy is based on the belief that: 1) Bitcoin has not yet reached its full potential. 2) Short-term price movements are unknowable.
You may disagree with #1 but I'd say you're delusional if you think you can predict Bitcoin price movements.
Of course, this is just my dumbed-down version of the strategy. For a more nuanced and rigorous version, it's better to read the source directly[0]:
> I type d that tyitle twice because I knew it was wrong the first time. Still wrong. w/e. GF's out at a lesbian bar, BTC crashing WHY AM I HOLDING? I'LL TELL YOU WHY. It's because I'm a bad trader and I KNOW I'M A BAD TRADER. Yeah you good traders can spot the highs and the lows pit pat piffy wing wong wang just like that and make a millino bucks sure no problem bro. Likewise the weak hands are like OH NO IT'S GOING DOWN I'M GONNA SELL he he he and then they're like OH GOD MY ASSHOLE when the SMART traders who KNOW WHAT THE FUCK THEY'RE DOING buy back in but you know what? I'm not part of that group. When the traders buy back in I'm already part of the market capital so GUESS WHO YOU'RE CHEATING day traders NOT ME~! Those taunt threads saying "OHH YOU SHOULD HAVE SOLD" YEAH NO SHIT. NO SHIT I SHOULD HAVE SOLD. I SHOULD HAVE SOLD MOMENTS BEFORE EVERY SELL AND BOUGHT MOMENTS BEFORE EVERY BUY BUT YOU KNOW WHAT NOT EVERYBODY IS AS COOL AS YOU. You only sell in a bear market if you are a good day trader or an illusioned noob. The people inbetween hold. In a zero-sum game such as this, traders can only take your money if you sell.
> so i've had some whiskey
> actually on the bottle it's spelled whisky
> w/e
> sue me
> (but only if it's payable in BTC)