Let's consider a few common everyday examples where paying attention to small details can have a positive effect on management performance.
Being on time
Simple as it comes. But, basic though punctuality may seem, chronically keeping employees waiting is one of those little irritants that sends a strongly negative message. It says: Your time is not as important as mine. And by extension, you are not as important as I am. While this may be technically accurate from an organizational standpoint, you can be sure of one thing: It's not a message any employee wants to hear. (Corporate memory: Is chronic managerial tardiness of this type pretty common? Quick answer: Yep.)
A word of praise
A little goes a long way. Research consistently shows that when it comes to praising, employees often just don't get enough of it. One recent study indicated that 36% of employees considered lack of recognition the top reason to leave their jobs. When one considers the amount of time and effort a simple word of praise requires (de minimis), it's surprising this is the frequent pain point it is.
Celebrating minor team wins.
Given how long many big important projects take, managers who stay right on top of the small stuff (a deadline met, a nettlesome deliverable completed) will help keep a team motivated and on track. When I was in the corporate world, I recall one post-merger integration of enormous systems project that took a massive team the better of a decade to complete. You can be sure in a project of that scope good managers were conscious of minor milestones... as motivation naturally flags when projects grind on year after year.
Being flexible
In a world where people are perpetually over-scheduled and short of time, showing some schedule flexibility can be a good easy move. Giving an employee a little time now and then to attend a daughter's ballgame or to visit an elderly parent can be greatly appreciated. As a manager you may often find employees working extra-diligently to be sure you realize they're not taking advantage of this highly valued time.
None of these are in any way the big strategic stuff they teach you about in MBA programs. But they can be a difference maker in terms of how effectively one performs in a management role.