There's a simple but excellent heuristic that consultants can use to ensure client satisfaction. It's called the "50/50 rule."
(Apologize in advance since I can't remember who first shared with me this idea).
The 50/50 rule means that you should devote half of your attention to results, and the other half to your client's experience. I love this idea because it translates in a very elegantly way that, while expertise matters, it is not enough to win the trust and loyalty of clients.
When we talk about value in the context of consulting, we're really talking about different questions with very different answers. You first goal will always be to deliver against expectations. Did you deliver what you were contractually obligated to, in the timeframe and to the budget that you've promised?
You do that by successfully applying your expertise to a problem. If you fail to deliver on your marketing promises, clients won't be happy.
But generating results is not enough. This is especially true in crowded or ultra-competitive niches, in which a number of consulting firms can deliver the same results as you do. How do you differentiate?
The bigger the number of consultants who can generate the impact and results that you do, the more customer experience matters. It is by providing your clients with a satisfying experience that you stand out, and set yourself apart from the crowd.
Do you propose new ideas? Have you ever challenged your client's assumptions about a project before starting? Do you show that you care?
An order-taker can be easily replaced - even if the desired outcome and results are being delivered.