There are many issues that can occur during the course of a campaign. Many have simple solutions, many others have complex issues, but regardless you still need to be aware of a problem to address it. A newly formed group will also tend to have more issues than a veteran one, where players haven't had time to work out their issues and get into the flow of things. What I've seen used, and used myself in these cases, is the idea of a postmortem. At the end of some milestone, you have your players look back over what happened and give their opinions.
Being On The Same Page
One of the big things in tabletop gaming is being on the same page. Players need to know what actions they can take and reasonably know what their odds of success is within limits. Dungeon Masters need to know what tools they have at their disposal and what players are willing to tolerate. All of this starts with an understanding between players and Dungeon Master that their concerns will be addressed. Communication break downs and differences of expectation are what postmortems give you the opportunity to address by having a structured system built in where players know they can be heard. You also don't want this kind of stuff to quietly simmer if your players have a problem.
It depends on your group and their experiences. Doing one per arc is very manageable and makes sure that player concerns are heard. However, earlier in a campaign you might seriously wish to consider doing one per session. This is especially true if you didn't know your players before the campaign started. The more distance there is between you, the more of a necessity there is. Eventually you can get to a point where you don't need them anymore, but I'd still recommend calling for one if concerns are brought up. The big thing to address in this case is if there's a difference of opinion. If fixing the problem for one will cause a problem for another, you'll need a clever compromise or to pick a side and have your players understand.
Taking Too Much Time
The issue that can often happen here is that the postmortems run too long. And especially at the start, this will happen. However, as Dungeon Master you can move on to other topics and then circle back around to the issues that result in a lot of discussions. If necessary, you can have that discussion outside of the session and take it into your favourite chat program or email. Having a structure that people are aware of is also extremely helpful in these cases. Have people mention what they liked (that way you know what is well received and maybe can be used again), what they didn't like (potential problems that need to be solved), and any other comments they might have. I find this setup works well as it touches on the aspects we are really after: what are the likes and dislikes of our players. It may also be an execution thing in some cases, and having that feedback is important.