It's easy. Each and every bet that you make is against the house advantage. Therefore, you are favored to lose each and every bet. If the house wins 48% of its bets and the player wins 43% of his bets (the rest are pushes), then those times when you raise your bet you will only win 43% of the time, and those times when you lower your bet, you will still only win 43% of the time. So your progression strategies of lowering and raising your bet are subject to the same house edge at all times, whether you are raising or lowering, makes no difference. You might as well just flat bet all the time, because all is subject to the house advantage. By flat betting, you won't get caught losing when you raise your bet, so you have a better chance of surviving longer.
Enter counting. Counting works because it can use information that has gone before in determining the size of your bet. Since lots of tens and aces are in the remaining cards, you know that the the advantage has temporarily switched to the player. Only counting lets you know when the player temporarily has the advantage.
With a progression, the information that went before, how many wins or losses, gives no meaningful data as to what the size of the bet should be, or who has the advantage, you or the house. That is because without counting all you know is that the player has the exact same chance of winning each hand on average no matter what preceded. Because ten wins preceded your current bet does not mean that a loss is imminent. No, the chances based on known information remains the same for each and every bet. For all you know, the count has remained at zero the entire time. That would mean you have only your average 43% chance of winning. The count may also have gone negative, giving you an even greater chance of losing, and it can remain that way the entire shoe. Just as in craps, the cards have no memory of what went before, that is, if you are not counting.
The concept is so simple that it is sometimes difficult to see. When you finally do see it, you wonder how you could have been so stupid. But don't feel bad; it's like an optical illusion. It naturally appears one way, when in reality it's the other.
Always remember. With dice, the chances are always the same each and every time you throw them (short of any manipulation on your part). That's why they say the dice have no memory. No matter how you bet your money at dice, the chances never change. Fifty sevens in a row does not mean a thing (except you're getting rich, lol), because each time you throw the dice you have the same chance of rolling a seven. With cards it's the same thing, except for card counting where you use what went before to shape your future strategy. Nothing else can work against the house advantage. 43% of the time you win, 48% of the time you lose, and 9% of the time you push. All of this is on average. It's knowing when you have the best chance to be in the 43% that pays off with card counting. Nothing else can do it.