He's maybe feeling a bit of pressure due to the superstar status expected after last season. Everything he does is heavily scrutinised and especially his finishing.
Was last season a one off ? Probably
The reason I say that is because no one here expected him to score what he did last year. These are his stats below from 2012/13.
2012/13 Basel. 50 Apps and 10 goals.
2013/14 Basel. 29 Apps and 10 goals.
2013/14 Chelsea. 11 Apps and 2 goals.
2014/15 Chelsea. 8 Apps and 0 goals.
2014/15 Fiorentina. 26 Apps and 9 goals.
2015/16 Roma. 42 Apps and 15 goals.
2016/17 Roma. 41 Apps and 19 goals.
2017/18 Liverpool. 52 Apps and 44 goals.
Last season was a career best by a mile and had he of produced a similar return the year before then, he wouldn't be here because of what they would of demanded for him. The lad is a winger with a good goal return, He's not a clinical striker. This season he has 3 goals in 8 Apps which isn't bad and probably more on par for his course. He has loads to go this season and while he might not hit 44 he will top 20 easy which will only be for the second time in his career.
He is working hard getting into positions and most of it he creates himself. He has had a few frustrating moments in front of goal but it was the same last year as well. I think because we aren't playing so well as we were last year Mo has been bearing the brunt of that like its his fault when It isn't.