Watched a depressing video about multiplayer matching-making systems in PVP games earlier.
How the matcher will often create a lot of information about someone and use it against them to keep them playing and paying, people just think it matches you against people of a similar level so you can have fun matches. In reality it's playing you.
For instance it will often calculate your preferred play times or how many matches you usually play, and then put you into matches it judges you will win or lose depending on what it's trying to achieve. Like they often will give you a much higher chance of failure for the first few matches to give you a feeling of a challenge and then far far higher chance of wins on the later matches so you feel like you had a tough few matches but you got into your groove and ended your day with great victories. Final matches of the day often dictate how you felt the entire playtime went, ending on a failure is bad for business.
All easy matches = bored, might quit.
All hard losses = demoralized, might quit.
All wins all day but last match before you quit for the night is a loss = fixate on the loss, might quit.
Ultimate goal 50/50 win/lose ratio, with wins being more likely at the end of your calculated play duration.
They will also tend to increase your chances of being matched against lesser skilled players for easy wins if you have spent money on the store recently, to give you a positive feeling linked to those purchases.
The worst one (you just know they do this on PVE games too) was matching very skilled players who owned cosmetics in groups with lesser players that were noted to be willing to spend money, directly to promote sales of those cosmetics to this cash cow player. Because lesser skilled players try to emulate higher skilled players they are impressed with, including buying the gear they wear to look like them.
Everything is money, psychology and playing the player these days.