As for the second paragraph, why would the sale spike be historic?
Also, if it sold steadily, that would mean there was no sales spike from Hot Boys. That seems unlikely.
Either way, it was flopping. It was not selling like the first album did.
Nowhere did I say there was NO spike from "Hot Boyz". What I'm saying it was nowhere as huge of a spike as you're making it out to be. You're going by the gold and platinum certification of the album. It got a gold and platinum certification February 2000. There's no way that album sold 500K and another 500K at the same time. Those are certifications for units shipped not sold.
And no, not selling what your first album sold isn't a flop by no means. By your reasoning, most artists are flops because for most, their first album is usually their biggest. Same goes for artists not outselling their previous album. Vol. 3 didn't do Vol. 2 numbers. FOMFBOMB didn't do IDAHIH numbers.
There's a difference between a slow burner and a flop. Slow burners are something that isn't an instant hit, but more gradual, which would describe what
Da Real World was. A flop is something that tanks upon arrival and rarely if ever picks up steam. Missy's
Da Real World debuted with around 1.5-2K more than the first week sales of her previous album. It took longer to reach the certification of the previous album, but by no means was it a flop.