On software and relationships
Another bug-bear is testing, a tricky subject since it is impossible to fully test all but the most trivial software (see the excellent book "the art of software testing") . However vendors vary dramatically on the degree of effort that they put in. At Kalido we have extensive automated test routines which run on every build of the software, which at least means that quite a lot of bugs get picked up automatically, though bugs of course still get through. Yet according to someone who used to work at Oracle, there it was policy to do minimal testing of software, where the testing strategy was described as "compile and ship". This certainly avoids the need for lots of expensive testers, but is hardly what customers expect.
However, customers can be unreasonable too. Their legal departments insist on using sometimes surreal contract templates that were often designed for buying bits of building equipment rather than software, resulting in needless delays in contract negotiation (but in-house corporate lawyers don't care about this, indeed it helps keep them busy). They can also make absurd demands: we recently lost a contract after refusing to certify that we would fix ANY bug in the software within eight hours, something which patently cannot be guaranteed by anyone, however responsive. A small vendor who won the bid signed up to this demand, and so will presumably be in breach of contract pretty much every day. Quite what the customer thinks they have gained from this is unclear. It is not clear why some customers behave in such ways, perhaps they feel like exacting revenge for previous bad experiences with vendors, or maybe some corporate cultures value aggressive negotiating.
From my experience on both sides of the fence, the best relationships occur when both parties understand that buying enterprise software is a long-term thing, in which it is important that both sides feel they are getting value. Vendors are more inclined to go the extra mile to fix a customer problem if that customer has been doing lots of reference calls for them, and actively participates in beta test programs, for example. As with many things in life, there needs to be a spirit of mutual respect and co-operation between customers and vendors if both are to get the best out of their relationship.