IT has always depended on strategic relationships with vendors and its heavy use of consultants to a degree that's unmatched in any other field of business. That's because no company can go it alone. The worst consultants believe their companies are smarter than their IT clients, instead of recognizing that they're extensions of their clients' resources. It's this arrogance that rightly irritates many IT professionals. IT is buying the culture, not just the consultants and project capacity.
Arrogant cultures make lousy partners and are in the rip-off business without realizing it.
Because they believe they're so much smarter, they make many mistakes that the more collaborative and respectful consulting firms don't make. Almost always, you see legal action against a consultancy where a senior partner sold the work and is rarely seen again. The junior partners, who do the real work, get in over their heads but don't know enough to realize it. First, find out if it's facing any current lawsuits. Second, understand the firm's economics.