inflation is only initially caused by money supply. once inflation expectations become embedded, it becomes a self-reinforcing perpetual motion machine.

e.g. imagine you negotiate a 13% raise because inflation was 13% last year (btw so did everyone else). congrats - everyone just guaranteed that they will have enough money to create 13% inflation next year, when the cycle will repeat

unemployment solves this because it's a "-100% raise" and takes spending power out of the economy

and inflation is generally considered bad because among other things it distorts markets for savings and loans