Title: 1990 New England Patriots season
Content:  Colts are the only NFL teams since 1940 to have eleven losses during which they never led in one season. The 1990 Patriots became the third team to end a season at 1–15, and were matched by the 1991 Colts the next year. They also tied the 1976 Tampa Bay Buccaneers for most consecutive losses inside one season (the Buccaneers lost all 14 games, with the NFL only adopting a sixteen-game schedule in 1978), a record later eclipsed by the 15-straight losing 2001 Carolina Panthers. It was then topped by the 0–16 2008 Detroit Lions and 0–16 2017 Cleveland Browns.
Title: List of National Football League longest losing streaks
Content: The longest losing streaks in the regular season in NFL history ; The longest losing streaks in the postseason in NFL history This article contains two lists: The Chicago Cardinals have the longest regular season losing streak, losing 29 consecutive games from 1942 through 1945. The Tampa Bay Buccaneers have the longest losing streak since the 1970 AFL–NFL merger, losing the first 26 games in franchise history in 1976 and 1977. The Detroit Lions hold the record for the longest postseason losing streak, dropping nine consecutive playoff games starting in 1991 – a streak which is still active.
Title: 2015 NFL season
Content:  game in NFL history (although it has since moved to the fourth highest scoring game).  In addition, the Giants' 49 points tied the NFL record for the most points scored by a losing team (with the Houston Oilers). ; Peyton Manning tied Brett Favre for the record of most regular season career victories all-time by a starting quarterback with the Broncos' 29–10 win against the Packers with 186 wins. ; Four teams started the season 7–0, setting a new NFL record. Week 9 ; For the first time in NFL history, three teams (the Bengals, Patriots, and Panthers) started the same season 
Title: List of all-time NFL win–loss records
Content:  two charter members of the NFL still in existence, the Chicago Bears have played the most games (1,384) and recorded both the most wins (777) and ties (42) in NFL regular season history, as of the end of the 2020 NFL season. Their NFC North divisional rival Green Bay Packers hold the highest regular season win–loss percentage (.569), with a 769–577–38 record through the end of the 2020 season. The league's other still-active charter member, the Arizona Cardinals, have recorded the most regular season losses (771), through the end of the 2020 season. The Tampa Bay Buccaneers maintain the lowest regular season win–loss percentage 
Title: 2012 Atlanta Falcons season
Content:  The 34–0 win over the Giants was the worst shutout loss to a defending Super Bowl champion team in NFL history. The next three worst were 27–0, 17–0, and 16–0, all by the Oakland Raiders in the same season.
Title: 2009 NFL season
Content:  The New Orleans Saints became the first team in NFL history to lose their last three regular season games and then go on to the Super Bowl and win.
Title: List of all-time NFL win–loss records
Content:  through the end of Super Bowl LV. The New England Patriots have the most playoff wins (37) and the highest playoff win–loss percentage (.638), with a 37–21 record, as of the end of Super Bowl LV. The Minnesota Vikings have recorded the most playoff losses (30), whereas the Cincinnati Bengals have the lowest playoff win–loss percentage (.263) with a 5–14 record. The Houston Texans have the fewest games played (10), wins (4), and losses (6) in NFL playoff history. When combining regular season and playoff win–loss records, the Bears hold the distinction for most overall games played (1,455), whereas the Packers have recorded 
Title: List of all-time NFL win–loss records
Content:  most wins (805) and the highest winning percentage (.571), with a 805–601–38 record through the end of Super Bowl LV. The Cardinals have recorded the most losses (780), and the Buccaneers hold the lowest winning percentage (.401), with a 294–439–1 record through the end of Super Bowl LV, a game which they won. The NFL officially counts and includes the statistical records logged by teams that played in the American Football League (AFL) as part of NFL history. Therefore, these teams' pre-merger win–loss records are accounted for. However, the NFL does not officially count All-America Football Conference statistics, despite the 1950 NFL–AAFC merger.
Title: 1976 Tampa Bay Buccaneers season
Content:  in a single season has been surpassed four times: by the 2001 Carolina Panthers and the 2020 Jacksonville Jaguars, who both lost fifteen consecutive games after winning their opener, the 2008 Detroit Lions, and the 2017 Cleveland Browns, the latter two being the only winless teams in a 16-game schedule. Twelve NFL teams since the 1976 Buccaneers have lost 15 or 16 games in a season, but the Buccaneers' 26-game losing streak from 1976 to 1977 still stands as the longest in modern NFL history. The aforementioned Detroit Lions have come the closest to matching the Buccaneers' losing streak, having lost 19 consecutive games between the last game of 2007 until finally winning in week 3 of the 2009 season.
Title: 1991 Indianapolis Colts season
Content:  The Colts were victorious only once in the regular season, finishing last in the AFC East, and their fifteen losses tied an NFL record that was initially set by the 1980 New Orleans Saints and tied by the 1989 Dallas Cowboys and 1990 New England Patriots in the previous two NFL seasons. The 1991 Colts had a much weaker schedule to play than either the 1990 Patriots or 1989 Cowboys, playing eleven games against teams with non-winning records, as against only five for the 1990 Patriots and four for the 1989 Cowboys. The Colts lost nine consecutive games to start the season before rallying to defeat 

Question: who is the most losing team in nfl history?
Answer: Arizona Cardinals.
Tampa Bay Buccaneers.