Liverpool’s season so far was summed up by their disappointing elimination from the FA Cup last week at the hands of Brighton and Hove Albion.The Reds labored for much of the game, with Roberto De Zerbi’s side coming from a goal down to record a 2-1 victory at the Amex Stadium.It was Liverpool's second loss to Brighton in the space of two weeks, having been thrashed 3-0 by the Seagulls on January 14 in the Premier League.Jurgen Klopp’s side has now won just one of their last six matches in all competitions and are out of both the Carabao Cup and FA Cup, which raises more questions about the club’s failure to beef up their squad during the January transfer window. Joel Rabinowitz@joel_archieOnce again, Liverpool remain the only big club on the planet to consistently treat the transfer window like an inconvenience rather than an opportunity to strengthen. twitter.com/FabrizioRomano…Fabrizio Romano@FabrizioRomanoJurgen Klopp announces Liverpool will not sign any other player in January: “Nothing will happen in this transfer window, not at all”. #LFC“It's all good with this squad”, Klopp added.81801265Jurgen Klopp announces Liverpool will not sign any other player in January: “Nothing will happen in this transfer window, not at all”. 🚨🔴 #LFC“It's all good with this squad”, Klopp added. https://t.co/l5RpW0dNONOnce again, Liverpool remain the only big club on the planet to consistently treat the transfer window like an inconvenience rather than an opportunity to strengthen. twitter.com/FabrizioRomano…Reds the biggest losers in transfer windowLiverpool are arguably the biggest losers of the recently closed transfer window, following the club’s relative inactivity. The only signing that walked through Anfield’s doors was Cody Gakpo, who is yet to register a goal contribution despite playing a number of games. That said, the Reds have been very unlucky with injuries this season, with Luis Diaz, Virgil van Dijk, Roberto Firmino, Diogo Jota and Ibrahima Konate all being ruled out due to injuries. However, the club’s biggest shortfall has always been in the middle of the park, where they lack both quality and depth. Gakpo is a decent signing, but that money would’ve been better spent on a midfielder.The Reds were the most inactive of the top six clubs in transfers and could come to rue the decision not to reinforce their squad as we enter the business end of the season.Sky Sports Premier League@SkySportsPLJamie Carragher talks about Liverpool's current situation and what they need to do between now and the end of the campaign to get back to where they were in previous seasons... 3084156Jamie Carragher talks about Liverpool's current situation and what they need to do between now and the end of the campaign to get back to where they were in previous seasons... 🔴 https://t.co/WA4xxLheaALiverpool left weaker as rivals strengthen their squadsKlopp’s statement in the aftermath of the team’s defeat to Brighton in the FA Cup was the biggest hammer blow to Liverpool fans. The German coach was blunt in his assessment of the club’s transfer business when he told talkSport:“No, no, nothing will happen in this transfer window. That’s it, all good.”What this means, however, is that the Reds have been left weaker than they were when the season started. They currently occupy ninth place in the Premier League, with the same points as Chelsea, but the Blues were very busy during the transfer window, spending in excess of €400 million to strengthen their squad. Even Arsenal, who currently sit at the top of the league table, made some shrewd moves by acquiring the services of Jorginho and Leandro Trossard. Manchester United smartly brought in Marcel Sabitzer to fill the void left by the injured Christian Eriksen and added Dutch striker Wout Weghorst to the squad.It is hard to see Liverpool catching up to their rivals and qualifying for the Champions League, who now boast better quality and squad depth.Liverpool have often gotten away with it in the past when their owners refused to spend, but this time the threat of their rivals leaving them behind is real. They could yet sink further as the season progresses after missing the chance to make their squad competitive.