but remember that if you order some miners which are delivered in the future - the hashrate difficulty may have doubled/tripled or even more before you even receive the hardware.
This is isn't a public secret, almost everyone knows that profitability always in a short time, but repeated always. That's why you can't find some advice like that. Or may this is referring to ASIC Miner, I have no idea.

If you still decide to go for it, good luck and have fun doing it
Thank you, I'm doing it, and I am fun.

This sounds like a bitmain/asic business adventure gone wrong?
Maybe, It can be!