If the 5th bet loses you have dug a serious hole 1+2+3+4+5=15 loss total.
If it wins at $2 you get back $10 for a loss of $5 total.

Flat bet is $5 total bet for 5 bets. $5 total loss if the 5th bet loses, but you have only risked $5 not $15. If it wins you lose $3 total for risking $5.

In the progression you have risked $15 and will lose $15 if the 5th bet doesn't win. If it does win, you have achieved a loss of $5 [instead of $15] for an outlay risk of $15. Crazy stuff!

Odds wise, you have been getting collectively shorter and shorter [not longer] odds the more you progressively bet.