Before you start ranting "You're just a noob" that doesn't know how to play, well I can't stop you from that, but I assure you I know fairly well how to use my armor, but that's the issue the most players are no Muppets.
They wont shoot a hulldown tank on the turret or a sidescraping tank.
The other Day I had muppets against me in my maus and they somehow didn't stop shooting me sidescraping, obviously some gold rounds found a mysterious angle into my cheeks. But even then I only bounced shy under 3x my hitpoints (8390).
Sometimes I have rounds in my maus with under 1k bounced even though I'm up front but people would rather shoot my ally.
Dropping down some tiers the armor layouts are not that reliable or the enemy ain't got enough alpha. Or you're against T10 that have enough Pen to go trough you like nothing.
And then there are of course the people that don't even bother to shoot standard against T8 and just squish you anyway with gold.
Source: https://www.reddit.com/r/WorldofTanks/comments/fp8krq/blocking_missions_are_really_hard/