Selling is a complex and dynamic human interaction. There are a lot of things that can wrong that can cost you a deal. But there are two that tend to dominate the "reason" category for losing deals.
1. Relationships matter
I have met and spent time with Matt Dixon and Brent Adamson from CEB, the authors of The Challenger Sale. They say that their research suggests that challengers, or those who are willing to challenge their prospective clients, major in challenging and minor in relationships, where they had the second highest scores.
Right now, there is a ton of market pressure driving companies — and the people that make them up — to be more transactional. The communication methods we use are less personal than the traditional methods. The sales processes we implement are more transactional than they should be. The drive to reduce costs across all segments of the business is causing companies to move parts of the sales function inside. And a lot of salespeople believe those processes are supposed to be transacting.
The more complex, risky, and expensive the solution you sell, the more you need relationships to succeed. Not going to meet your client because it is a plane trip away is a decision to ignore how important relationships are. The trouble is your clients will allow you to be as transactional as you want to be.
Don't be surprised when you lose because no one really knows you. If you think that being known, liked, and trusted isn't important, try to sell without them.