Hello IH working in teams, what's the most annoying thing in your pipeline?

Hello everyone :)

So I am currently creating a (yet another) productivity manager app, that focuses more on group/organizational level interactions. It's a fun side project, mostly for my personal use, but having additional ideas from other people won't hurt, right? So, if you've been working/managing a team, what do you think is the most annoying/challenging part of your daily operations?