Short detour to give a simplified example of #ProportionalRepresentation:
Votes are cast in five ridings:
Blue: 40%
Red: 30%
Orange: 20%
Green: 10%
With single members elected, all five ridings elect Blue, giving a false majority with only 40% of the vote, and 60% of the votes wasted with no representation.
With five members elected in one large riding, we'd get two Blues, two Reds, and one Orange, with 90% of the votes getting some representation.