Arguments for meeting at least all P1 checkpoints

Hello all,
I am looking for arguments explaining to people why it is essential to meet at least all WCAG priority 1 checkpoints. 
WCAG 1.0 only says : 
Priority 1: "A Web content developer must satisfy this checkpoint. Otherwise, one or more groups will find it impossible to access information in the document. Satisfying
this checkpoint is a basic requirement for some groups to be able to use Web documents."

I am looking for concrete explanations showing the impact of not following the checkpoints for users with disabilities. 
Concretely, what does it mean for users with disabilities, if checkpoint 1.4, for example, is not satisfied? 
Which users are concerned? Why?
Thank you in advance
Best
Sylvie

Received on Monday, 5 March 2007 14:57:31 UTC