Clients often look for low bids when hiring a contractor. If one bids $100,000 and the other bids $75,000, they'll go with the contractor who costs $25,000 less.
This makes sense, of course, but it can lead to some problems, especially when clients and contractors aren't envisioning the same results, the same level of quality, and the same finished product. The client thinks that the quality is exactly the same with both bids, and he or she is happy to save money. The contractor thinks that the client isn't really "saving" money at all. He or she is just paying less for a lower-quality job.