The Reds goalkeeper has been pleased with his side's results against the "big" teams but admits they have not been consistent enough.
Simon Mignolet has told talkSPORT that he the players are not happy with how their Premier League campaign has gone, admitting that they have not been consistent enough in their performances and results.
Jurgen Klopp's side secured their place in the Europa League final on Thursday night with a 3-0 victory in their semi-final second leg against Villarreal at a raucous Anfield.
The Reds also reached the final of the Capital One Cup back in late February, but they were beaten on penalties by Manchester City after a 1-1 draw.
In the league, however, it has been a mixed season for the Merseyside club. Under Brendan Rodgers they won just three of their first eight games of the campaign, and though they have improved under Klopp, they still sit only eighth in the table with just three matches remaining.
Part of their problem has been consistency - though they have done the double over Manchester City in style with 4-1 and 3-0 victories as well as beating the likes of Chelsea and newly-crowned champions Leicester City, they have suffered defeats to bottom-half clubs such as Swansea City, Watford, Newcastle United, and Crystal Palace.
Mignolet admits it has been a frustrating domestic campaign for the Reds and stressed that they must work on becoming more consistent to achieve success next season.
"We’re not really happy with the Premier League. We’ve done really well against the big teams, but we should be doing that on a consistent basis, and that’s something we need to take forward."
Liverpool have a hectic fortnight ahead of them, facing Watford, Chelsea, and West Bromwich Albion before their Europa League final against Sevilla on Wednesday, 18 May.