Indeed, when talking about Champions League matches, the results are always unexpected. Clubs that perform poorly in the Domestic League are actually focused on the opportunity to do better in the Champions League. Therefore, Liverpool should not underestimate Inter who have indeed performed poorly in Serie A. Moreover Arsenal will get a fairly difficult opponent like Atalanta, they were the Europa League champions last season and in terms of Atalanta game is strong enough to make Arteta game plan difficult.
Underestimating the opponent is the biggest mistake a club can make, especially when they are competing in the UCL which always presents unexpected surprises. Inter were the Scudetto winners last season, they are also very experienced in the Champions League. Even though Liverpool is currently in their best form after successfully sweeping all points in the three games played in the EPL, there is no reason for them to underestimate their opponents, especially a team like Inter. Liverpool must learn from the result achieved when they were defeated by Atalanta last season in the Europa League, every match must be considered important even if the opponent they face is weaker than them.
In my opinion, Atalanta are not very strong this season, they have just suffered two consecutive defeats in Serie A. Arsenal, who are performing well, are one level above Atalanta, but Arteta must remain focused by fielding his best squad in order to achieve victory. Atalanta were so easy to beat in Serie A, they are very difficult to repeat the success achieved in the Europa League last season. Arsenal have always been consistent in maintaining their performance, especially this season their motivation is increasing to win the title, so Atalanta will not be too difficult for Arsenal.