You make X in dirty money, then invest it into a cool sounding company promising groundbreaking stuff that has a bunch of big known investors on board already. If the company does well, you take the clean money out with a nice profit on top. If it doesn’t work out, hopefully you pulled out at a level where you lost some money but not much. And it still returns you clean money at the end, so the goal is accomplished.

Typically, this kind of money laundering is done through retail businesses like restaurants and such, but it is way easier to just drop those money as an investment into another company, rather than maintaining your own retail business. Plus, the amount of money you could launder by investing is way higher, since it isnt as suspicious to drop a few hundred millions on a startup investment, as opposed to claiming that your small restaurant that is almost always empty is bringing you tens of millions per year.