I read this short blog post on the Harvard Business Review website today and I agree with the author's fundamental point. Consultants can be very useful to an organization but if you hire one then you should manage them to make sure you get value for money. In my experience problems can start even before the consultant is hired. The absolutely critical step in any procurement process is to know what you want to buy. If you don't know what you want then you leave yourself open to the sort of cross-selling and scope creep described in the bloq. Sadly I have been witness to situations where a manager has decided that a consultant is the solution to a problem and hires someone without ever trying to describe what the problem is and what kind of solution was required.
Also, in the real world, consultants are sometimes hired because a manager is expected, obliged or even forced to hire one. Major outsourcing deals and PFI contracts involve lots of consultants each with their own area of expertise. It reminded me, though, of the time I was managing the outsourcing of the contract services division of a London borough. We were advised by an external firm of solicitors and in practice we had to be because the council only had one qualified solicitor in post at the time and they had lots of other things to do. Anyway, I was asked by my boss if I wanted some support in the form of management consultants or financial advisors. I was loathe to hire anyone because if they always agreed with what the lawyers said then they weren't needed; and if they disagreed with the lawyers, given that we were talking about a contract and not a set of accounts, I was going to take the lawyers' advice. The moral of this? I could easily have spent tens of thousands of pounds with one of the big firms of consultants with the full support of my boss. It would have covered my back, too. But it would have been a waste of money because we did not need them. Knowing what you want to do is all well as good, but you need to know when you don't need to buy as well.