Consultancy can be a good thing - or a bad thing, depending on which consultants are brought in, and why.
It is one of the oldest tropes that consultants are brought in to tell people what they already know - and there is some truth in it. But when it comes down to it, consultants are asked to do this job because they are external - and they can tell truth to power without being seen as having an internal political agenda.
As consultants, we are brought in by clients to provide skills that they don't have in house. There tend to be two reasons for this. Either they want us for a short period to do a specific task which wouldn't be worth them recruiting for, or they are looking for a longer term relationship - in which case we can offer them access to a wider pool of talent than they would get by recruiting in.
Finally, I have worked with a great number of talented folks at all stages of their careers. Almost without exception, every one of them has been passionate about their work, and determined to do the best job possible for the clients. And a number of them have left us to work directly for clients.
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Then what about these consultants? Well, they don't need to actually solve the problem either. They just make various plans and present a slide deck to management at the end and collect a check. Whether the plan works or not doesn't even matter here, because the consultants got paid already and are on to the next job, the manager looks good because they brought in a consultancy, and if shit fails in the next three years well its no ones fault, because management will act like they did everything right bringing in the consultancy and will cut other staff first.
Consultancyism is everywhere these days. Its the next big thing in emerging markets which is even scarier and only a fig leaf away from imperialism with the terms of how some of these deals are struck, always to the benefit of capital with the people seen as a resource for extraction or exploitation. Consultancyism probably also encourages an unhealthy mercenary outlook on life. Never taking pride in projects because they are never your projects in your community, they are just jobs elsewhere to make some money.