Because that's what they get told it will do. I was at a church that was looking to upgrade it's sound and video equipment. The current system was a 16 channel analogue desk, with no one operating it, and a pc controlling the projection of song words on a screen. The inputs were 4 radio mics, though normally only one was used, and a music group consisting of an electric piano and drum kit and 4 microphones for vocalists. The congregation usually numbered 50-60 with an average age of about 60. Despite a number of appeals no one wanted to run the sound system and only two were willing to run the screen. They had had an company recommended to them by the Diocese, who at the insistence of the Organist / Music Director, were recommending a wireless digital mixer and also a wireless projection system. They were told that the digital desk could have compressors on all the inputs so no one would have to control the volume sliders, and that the installation company would provide a two hour training session that would make them experts in running the system. In the end, and grudgingly, the organist and church council were told that they should talk to me, having been involved with sound systems in churches for many years, also personally running a digital desk for 18 years. During the discussion I pointed out that this system was well beyond what they needed and that the training was not going to make them experts as they struggled to operate / fault find on their existing system. I was told that the suppliers must know what they were talking about as they were experts and had been recommended to them. People did not seem able to grasp that they were sales men and that they had to make money. The best response I had was that it must be the best as it was digital, this came from a lady who had her husband print out emails so she could read them. These are the people that are making the decisions.