The Buffalo Sabres hold the longest current postseason drought of any NHL team at 9 seasons - the last time they made the playoffs was in 2011. Even during the 2020 postseason, the Sabres were included in the mere 7 NHL teams that did not officially make the qualifying round. Additionally, the last time they won a first round playoff series was in 2007. A team's success is based largely upon their postseason success, and the fact that they hold the longest current drought shows that, within the last decade, they have performed incredibly poorly compared to the rest of the league.
All of the Sabres' history should be considered when determining their success, and they have made it to the Stanley Cup finals twice. Determining a team's performance within that small sliver of team does not truly show the entire picture of the franchise, and there are many teams throughout all of professional sports that have had little success within the last decade. Franchise success is about considering every season, not just a few of the most recent ones.
[P1] Franchise success is based on postseason success, and a team with a sizable drought in its respective league should automatically be considered the least successful. [P2] The Buffalo Sabres have the longest current postseason drought in the NHL, and they've had little playoff success in the last 13 years. [P3] The Buffalo Sabres are the least successful sports franchise.
Rejecting the premises
[Rejecting P2] Just because the Sabres have not had playoff success within the last decade does not necessarily encapsulate their entire franchise history. [Rejecting P3] The Buffalo Sabres should not be discounted for these reasons.