A manager who lunches with the same staffers all the time to the exclusion of others risks having his leadership skills questioned.
Here's the content of an email I received recently:
What would you make of supervisor who goes to a amusement park with several subordinates, or who goes to lunch every day with them to the exclusion of other subordinates? Can such a person be trusted to reliably evaluate their performance? When does a manager stop being a manager and cross the line over to best buddy? Seems to me that going to an occasional lunch or happy hour with subordinates is a good thing, but at some point doesn't too much of a good thing become an unprofessional thing?
Here's the image that came unbidden to me after reading your email: A manager and two staffers walking in the office laughing, all windblown and carrying huge stuffed animals they won playing Whack-a-Mole, while one lone employee sits at his keyboard tirelessly tweaking code.
I know this is an extreme example, but I use it to illustrate what can happen when you're dealing with something that is open to human interpretation. Not only do I see that manager subconsciously distancing himself, and vice versa, from the guy who didn't go on the outing but I also can't see that manager-even if he is infused with superhuman levels of objectivity-being able to later look one of the two employees who went on the outing in his cotton-candy-stained face and telling him he needs to step up to the plate or he's going to be fired.
If the outing was a rare reward for a high-performing team but the one guy just didn't want to go, then that might be fine. But if it happens all the time, in addition to the lunches, with the same people, then there's a problem.
It's difficult sometimes for a manager to separate from the team, especially if the manager was promoted from within the ranks. But you really have to distance yourselves to some extent or you're opening yourself up to all kinds of risk. It's part of the job.
For one, if you have lunch with the same employee or employees all the time, you're bound to communicate with them on a different level. The more those employees are around you, the more they indirectly pick up on how you like to see things done, while the other guy may not have the slightest clue.
One guy I knew worked for someone who hired a friend and they continued their friendship after hours-having dinner with each others' families, meeting for drinks after work. Every time a plum assignment came up, it was the manager's friend who usually got the opportunity to take it on. The manager didn't make the choice because of his friendship but because he knew the other guy so well that he knew he would ace the project. The problem with this is that other employees don't get the chance to prove themselves.
Even if the "outside" employee is legitimately not doing well and you have to mention it to him, do you not think some part of him is going to blame your closeness with the others on your perception of him?
I would recommend a friendly closeness with all team members but you must draw a line.