Matching against 5 man pre-mades as groups of solos, multiple times in a row.

How is this even allowed to happen?

It creates a cheesy and crappy experience especially playing as support as you can't pull anything off after early game. It should be impossible per matchmaking to place a 5 man up against a group of solos, or excuse me one time there was a duo and 3 solo players.

Can a member of Riot explain the incompetence from the games matchmaking? Is it a bug? A coder? A leadership decision? Where is the screw up?