Perhaps it is. But does he know it? Have you told him? In teamwork, as in marriage, implicit expectations create tension that's bound to explode at some point. Disarming that bomb is as easy as saying “could you?”
Some jobs have tighter-defined responsibilities than others. Across the spectrum of employment that's obvious—if you're, say, a train driver your job is to safely steer a few thousand tons of steel, carrying a few hundred human lives to their desired destinations. If you're an artist, there's much less specificity.
Even within the IT industry there are vast differences in job descriptions. A DBA is tasked with maintaining dabatase servers, often including developing data models and optimizing queries for efficiency. For a developer, things get a bit more blurry, being expected not just to write code, but these days often also setting up server infrastructure, configuring deployments, monitoring service health and, perhaps hardest of all, understanding and catering for user needs.
Then there are the managers, whose job descriptions are becoming increasingly confusing. Ensuring timely delivery, supervising quality, motivating their reports and caring for their career development. Everybody nods their heads in agreement on those, but what do these mean in practice?
In the (inherent) absence of specifics in one's listing of responsibilities, both the manager in question as well as everyone around them will develop their own image of what these should be. In particular, their reports will have varying expectations. Some will want them to be a communications bridge, others will prefer communicating directly. Some will want vision and guidance, others will want to have their own say. (I'm singling out managers here because of the evidence of the problem here, but the same concerns every job with a blurry description.)
The issue? Nobody tells them! The manager have their own view on responsibilities, obviously, and will execute against those. (Plus there are the manager's managers to cater for.) They will, regretably, often not sit down for a frank conversation with their team to talk out what everybody's role is. The result is frustration buildup. Reports holding watercooler conversations, complaining about their manager not leading this, not reacting to that, not talking to someone, etc. And they won't tell the manager because they feel it's inappropriate or for fear of retaliation.
I made a sport of calling out these situations. My lovely wife had thaught me from the outset of our relationship that if either of us wants the other to do (or not to do) something, we better voice it. Otherwise it'll pile up over time, explode at the least opportune moment, causing irreparable damage.
It's the same at work.
Take your manager out for coffee (if it's your first time, the setting should help loosen up everybody), then tell them: “Bob/Kathleen, could you ask our CTO for help with resolving the issue we're having with this vendor? Could you tell me how you see our priorities for the next three months?” No “I expect you…", “it's your job to…” crap. Just a human to human request—firm, direct, but very much considerate. You'll be well on your way to deflating the baloon of unmet expectations that would've blown you both away when (not “if”) it popped.
*[DBA]: DataBase Administrator *[CTO]: Chief Technology Officer