#3 Andy Carroll

Liverpool's most expensive signing at the time, Andy Carroll, is often mentioned as one of the worst deadline day transfers in the history of football. He joined the Reds for £37 million in 2011 and was signed along with Luis Suarez to replace Fernando Torres upfront, who had departed for Chelsea that winter.
Carroll's experience in the league with Newcastle, coupled with his strength and heading ability, was seen as a safe bet.
However, his performances never lived up to expectations, and excluding a couple of goals in crucial moments, Carroll was a flop in front of goal for Liverpool. He managed to score just 11 goals in 58 appearances for the club.
With the arrival of Brendan Rodgers at the helm, Carroll was informed that he was surplus to requirements. As such, he subsequently departed for West Ham after spending just 18 months at Liverpool.
#2 Mario Balotelli

Not many signings have proved as controversial for Liverpool as Mario Balotelli. The Italian had a mixed reputation while coming to Anfield. He was seen as a promising young talent during his youth years at Inter Milan, but was always mired in controversies. Later on, during his Manchester City days, he became known for his impulsive and arrogant behavior and poor disciplinary record.
He was signed as a direct replacement for the departing Luis Suarez, with Brendan Rodgers himself accepting that it was a gamble from his club to put faith in Balotelli.
The Italian certainly lived up to his infamous reputation at Anfield. Not only was he unable to perform for Liverpool on the pitch, but he was also publicly involved in dubious behavior off the pitch. He was fined by the club for posting anti-semetic content and was even criticized by the manager for swapping shirts with an opponent during half-time.
Balotelli managed to make just 16 appearances in the Premier League for the Reds, scoring a solitary goal. He was loaned back to AC Milan after just one season and was eventually sold to Ligue 1 side Nice in 2016.
#1 Lazar Markovic

Among the plethora of signings made by Liverpool in the post-Suarez era, Lazar Markovic was one of the most disappointing ones. He was signed for £22.5 million from Benfica when he was just 20 and was considered a bright young prospect.
But things did not go according to plan for the youngster. On his European debut against Basel, he earned a straight red card for flicking his fingers in the face of an opposing player. This was a subtle indication of his time at Anfield.
He was extremely slow on the ball and gave it way too cheaply in dangerous positions. As such he was always kept on the fringes of the first-team for the rest of his Liverpool career. He managed to score only three goals in 34 appearances for the club and was only called up by Brendan Rodgers when the manager had no other choice left on the bench.
Markovic was loaned out to Fenerbahce after just one season to gain some game time as the club did not want to see the money invested in him go to waste. But after a variety of loan spells ranging from Hull City to Sporting Lisbon he was unable to impress the people at Anfield.
With no team ready to meet the £16 million price tag Liverpool set for him, Markovic saw his contract with the Reds expire in 2019. He subsequently joined Fulham on a free transfer. The 27-year-old is now back in his homeland in Serbia and represents Partizan Belgrade.