Over the years, Arsenal have been renowned for buying raw talents for a bargain and developing them into world-class players. Arsenal have seldom splurged in transfer windows and often make signings after meticulous scouting.The signings of Thierry Henry from Juventus for £11 million, Dennis Bergkamp from Inter Milan for £7.5 million,and Patrick Vieira from AC Milan for £3.5 million are some notable examples in this regard.Top five players whose careers floundered after arriving at ArsenalIn recent times, Arsenal have signed a few players who failed to cope with the pace and physicality of the Premier League, though. These players joined the north London club with a weight of expectation on their shoulders but failed to live up to their hype.They suffered from massive dips in confidence and were never able to rejuvenate their careers even after securing moves away from Arsenal. On that note, let's take a look at five such players whose careers went downhill after joining Arsenal.#5 Shkodran MustafiShkodran MustafiArsenal fans were thrilled when the club signed Shkodran Mustafi from Valencia for £35 million in 2016.After years of defensive woes, the Gunners finally spent big to sign a top-quality defender. Mustafi was a prominent player for Germany in their victorious 2014 FIFA World Cup-winning team. He was also one of the best defenders in La Liga during his two seasons at Valencia.Shkodran Mustafi made 159 appearances in all competitions during his four-and-a-half season stint at Arsenal, But he was often criticised for his rash decision making and inconsistent performances.Eventually, both parties agreed to mutually terminate their association in February. Mustafi joined Schalke, who got relegated from the Bundesliga last week.Schalke, featuring Sead Kolasinac (on loan from Arsenal) & Shkodran Mustafi, have been relegated to the 2.Bundesliga, the second division of German football, following their 1-0 loss away to Arminia Bielefeld tonight. #afc pic.twitter.com/ZZ0mvFHM52— afcstuff (@afcstuff) April 20, 2021#4 Mathieu DebuchyMathieu DebuchyMathieu Debuchy enjoyed a scintillating campaign with Newcastle United in 2013-14 before he made a move to Arsenal.Debuchy had evolved into one of the best right-backs in the Premier League prior to his arrival in North London; he was also a regular for France.🚑 If it wasn't for his injuries, could Debuchy have made it at Arsenal?👇 Let us know what you think! pic.twitter.com/K8CGWf1C5D— AFTV (@AFTVMedia) July 4, 2020Arsenal signed Debuchy to provide competition to Hector Bellerin and to add some much-needed experience to their backline. The right-back, though, made just 30 appearances in all competitions during his four seasons at the club.Mathieu Debuchy spent the 2015-16 season on loan at Bordeaux, who didn't exercise the option to sign him permanently at the end of his loan spell. The Frenchman subsequently joined Ligue 1 club St. Etienne on a free transfer two years later.