I guess, but there are some all-time great series with relatively weak first seasons, e.g. Halt and Catch Fire and The Leftovers.

This doesn't filter out the series that start off strong with no contingency plan to get picked up, then they get signed to 2+ more seasons, go "ah shoot we blew all our story ideas in season 1" and slow play 3 episodes worth of content for an entire season. So. many. like. this.