Handicap tracking season

This is the first season I have tracked an index, so there are some things I still don't understand. In southeast PA, the season ended 11/1 and doesn't start again until April. I don't understand the purpose of the season ending. winter conditions are tough for scoring, but if you can put up a good score I don't understand why it wouldn't want to be counted. Can someone explain the rationale?

It's usually because of course maintenance. With temp the boxes, courses using two holes on the greens to rotate between groups and such the courses don't play as the scorecard states. If you play a round of golf somewhere else where it's still a hdcp season that round if entered will be counted in your index