In B2B relationships, even the most purely contractual ones, a major source of strain is that both parties can’t agree on the solution. This happens when you’re trying to close a sale. It comes back to haunt during the development and deployment stages.
But you know, maybe you should’ve seen it coming even while you were still qualifying your software sales leads. Are you doing things the way the client wants or do you take pride in your own way of identifying potential customers? Either way, the attitude could’ve been an indicator of any future strain in your business relationships.