Manchester City and Real Madrid always give a lot of importance to their domestic league and Champions League but we don't see that in case of Arsenal. Arsenal may take the English Premier League tournament very seriously but they are not too interested in the Champions League tournament. If they had given more importance to the Champions League tournament, their performances in the Champions League would not have been so bad on a regular basis, while in the English Premier League they are rightly second in the points table.
Arsenal are just beginning to pick form in the premier league as they weren't title contender before but for the last two seasons, they have been the only one chasing Manchester city. I think Arsenal wants to win the premier league first before they start concentrating on the champions league as it would be much easier to win the premier league than to win the championship league. The champions league has alot of heavyweight clubs that arsenal can't comfortably win. There's Real Madrid, Bayern Munich, Manchester city and Liverpool is right there above them when it comes to champions league therefore winning the premier league should be their priority first.
Every team of course wants to do well in every tournament and try their best to do well but I haven't noticed much of Arsenal's activity in the Champions League tournament. Arsenal have only focused on the English Premier League even though they have not been successful there in the last two seasons. If you want to do well in a tournament like the Champions League, you have to prepare in advance, but we have not seen Arsenal from Arsenal's side. Each season only strengthens the starting XI lineup but Arsenal lag behind all other teams when it comes to replacing them when the starting XI is injured. As the transfer window is still open, they need to buy players who can provide good support in case of injury to the starting eleven. If this is how the team is built, at least Arsenal will do much better than any other season in the Champions League.