Many have criticised the Three Lions' performance levels across the tournament given their lacklustre displays against the likes of Slovenia, Slovakia and Denmark, but memories of those games will fade quickly should they win the competition.
Southgate's tenure has yielded more appearances at major international tournament finals than every other manager in the history of England's senior national side combined.
However, the reality of modern international football and the quality at Southgate's disposal means that anything other than an English victory on Sunday should be seen as failure rather than success.
Here, Sports Mole explores why England must win Euro 2024 if Southgate's tenure is to be seen as successful.
Quality of English players
The first important factor to note is that Southgate has an immense array of talent at his disposal that few national team managers anywhere can boast.
Some have labelled this group of players as a golden generation due to the fact that they have consistently reached the latter stages of international tournaments, including a first ever European Championship final appearance at Euro 2020.
England record goalscorer Harry Kane is undoubtedly one of football's finest strikers, and despite his middling performances at Euro 2024 so far, he can point to the fact that he has scored or assisted 316 times in domestic leagues in his career.
Others such as Real Madrid's Jude Bellingham are likely to be in the race for the Ballon d'Or, while the likes of Trent Alexander-Arnold, who some consider to be among the world's most creative players, have often struggled for game time given the level of talent in the squad.
At the very least, Southgate does deserve credit for helping to foster an environment where these exceptional players have formed a cohesive unit inside the England camp, in contrast with past generations that were known to harbour a dislike for one another.
Poor quality of international football
A rebuttal to the argument that Southgate should be expected to win major international honours, given he has inherited a strong squad of players, would be that previous generations have failed despite their own immense talent.
Indeed, since England's World Cup win in 1966 the national team has only reached two major tournament finals, both under the leadership of the current manager.
However, while this rebuttal is valid to an extent it misses key context, most notably that the level of the traditional top teams in international football has declined in recent years.
Brazilian legend Ronaldinho recently criticised the national team and insisted that he would not be watching any games due to the side being unrecognisable, a sentiment which was shared by many during the current Copa America.
Elsewhere, prior to Euro 2024 Germany had failed to reach the knockout stage of the 2018 Russia World Cup after finishing bottom of a group that also consisted of South Korea, Mexico and Sweden.
Following this, the Three Lions proceeded to eliminate Germany from Euro 2020 in the round of 16, and at the 2022 Qatar World Cup the Germans were also knocked out after finishing third in a group that featured Spain, Costa Rica and Japan.
Others such as Belgium have massively underperformed in relation to the talent at their disposal and their current team is, in the words of Kevin De Bruyne, too old.
Even at Euro 2024, despite France boasting a squad that is arguably more talented than England's, Les Bleus only scored one open play goal in the tournament, and the fact that manager Didier Deschamps has 'only' won one World Cup during his time in charge is disappointing.
Fellow finalists Spain have only just emerged from the long period of mediocrity that followed their unprecedented success earlier in the century, when they won two European Championships and a World Cup between 2008 and 2012.
The weaknesses of these nations makes the current expectation of winning Euro 2024 more reasonable, and with this additional context in mind, the fact that Southgate is yet to win a major tournament should be of serious concern.
Previous failures at major tournaments
Another reason why England must win Euro 2024 if they are to be remembered as successful is that it is arguable that Southgate's side have underperformed considering the level of opposition faced in major tournaments.
For example, at the 2018 World Cup England finished second in a group that consisted of Belgium, Panama and Tunisia.
Southgate's team lost to Belgium, and required a stoppage-time winner from Harry Kane to beat Tunisia.
In the knockout stage, England were taken to penalties by Colombia in the round of 16, before they then defeated Sweden 2-0.
The Three Lions were later beaten 2-1 by Croatia in the semi-final after initially taking the lead through Kieran Trippier.
That result should be seen as a significant failure by Southgate considering his tactical decision to drop deep and allow Croatia to attack the penalty area proved costly.
To make matters worse, England also lost their third-place playoff against Belgium - a second defeat of the tournament to the Belgians.
Considering this, it is difficult to view Southgate's 2018 World Cup as an exceptional achievement when the realities would suggest otherwise.
As for England's Euro 2020 showing, they topped a group that consisted of Croatia, Czech Republic and Scotland, although they did fail to beat the Scots at Wembley.
This was not an especially impressive return, but was the minimum expected achievement given the level of opposition.
Some point to England's victory against Germany in the round of 16 as a particularly noteworthy result under Southgate but, as discussed previously, the Germany they faced were a particularly weak iteration.
A 4-0 victory against Ukraine and a 2-1 win against Denmark saw the Three Lions reach the final, a game played in front of a large English crowd at Wembley.
However, despite taking an early lead Southgate once again failed his side tactically, and England allowed their opponents to gain territory closer to their goal.
His decision to surrender possession and prioritise defending the box was particularly baffling considering the England squad had the players needed to threaten the Italian defence.
Centre-backs Giorgio Chiellini and Leonardo Bonucci lacked pace, and if Southgate had instructed his team to be more aggressive they may have had greater success during counter-attacks, but instead his tactics enabled the pair to push into England's half as the game went on.
England's Euro 2020 campaign should not be seen as a success, but rather an enormous failure on Southgate's part to take advantage of Wembley Stadium, a favourable knockout path and a vulnerable opponent in the final.
The final of Euro 2024
Ahead of the final of Euro 2024, it is fair to say that Spain, not England, are seen as favourites.
While this is a reasonable assessment given how both sides have performed at the tournament so far, it is still a damning indictment of Southgate and his inability to make the most of the squad at his disposal.
Having struggled their way past Serbia, Denmark, Slovenia, Slovakia, Switzerland and Netherlands, the Three Lions' pathway to the final has not exactly been the most challenging.
Spain have faced far superior opposition - Croatia, Albania, Italy, Georgia, Germany and France - en route to Berlin, so it is even more remarkable that such a performance delta has been seen between the two finalists so far.
Having said that, performances will matter little if England win Euro 2024, but if they lose on Sunday then simply reaching another final cannot be considered a success.
Given the quality of players that Southgate has had and the smooth pathways that have been afforded to his side over the years, England must win Euro 2024 if Southgate's tenure is to be remembered positively.
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