Middle Management has taken a hit over the last couple of decades, seen as a needless layer and targeted during downturns and 'right sizing' exercises.
Middle management, however, has survived. Even when it's eliminated it will eventually creep back into organizations as they realize they need this layer, particularly in large organizations.
While smaller organizations can operate with a flatter organization structure, the larger you get, the more layers you need. This is particularly true when managers have a wide range of functions under their responsibility. If every direct report does the same thing, perhaps just for a different geographic area, span of control and scope can be broader. But if you have wide, diverse set of responsibilities, it is harder to manage broader span of control and the middle management layer becomes more important to a smooth, functioning organization.
It's a simple algorithm since as managers we can only deal with so much scope and so many direct reports before we become bogged down in details and aren't able to do our real job: managing and leading resources to achieve a goal.
And yes, I said 'leading' since leadership is an important part of your job, even if your title has Manager in it and you thought only senior executives were leaders in your company. That leadership responsibility implies strategy, planning and implementing initiatives, improvements, changes and approaches that make the 'managing' part of the role easier and more successful for your company.
And how can you do those things if you are dealing with a broad scope and many resources who all need a slice of your attention. Where do you get the thinking and planning time you need, much less the time to develop, sell and implement your changes internally?
The other reason middle management is needed is to filter the s#@t that flows upwards from your staff, their staff and the customers and suppliers you probably deal with. You also, frankly, need to filter the s#@t that flows down from the corporate office - you know, the ones who say they are 'here to help'.
Unfortunately, corporate offices are there mostly to create 'off the rack' initiatives, policies and procedures for the entire corporation and expect you to follow them even when they don't really work in your area, country, with your staff, suppliers or customers. They mean well, after all, they are simply trying to introduce consistency that creates efficiency, but you end up having to deal with it and moderating the impact on your team, possibly customizing or re-imagining how to make it work in your area, etc.
So, if you work for someone in the 'middle management' group, consider what they have to deal with before you assume they are a useless management layer. After all, you aren't in their shoes and shouldn't judge - especially if you aspire to be promoted to their position.
If you are in a middle management role, take the time to explain the value of your role and what you do for the team under you to insulate them from things that would only distract them from achieving their goals, and how you give them the support and tools to get the job done and be successful, not only for your company, but for their careers.
Understanding is the most important part of accepting, and when your team understands your role, they may even be able to help you do it better for everyone's benefit.