Section 508 is an amendment made to the Rehabilitation Act of 1973 by US Congress to make their electronic and information technology accessible to people with disabilities. 

Section 508 requires that federal agencies and private organizations that receive government funding make Information and Communication Technology (ICT), such as technology, online training and websites, accessible to people with disabilities. This means that federal employees with disabilities are able to do their work on the accessible computers, phones and equipment in their offices, take online training or access the agency’s internal website to locate needed information. Section 508 also ensures that a person with a disability applying for a job with the federal government or a person who is using an agency’s website to get information about a program, or completing an online form has access to the same accessible information and resources available to anyone.

1. Government agencies
2. Private federal contractors
3. An organization that bids for government contracts

1. Cultivates an inclusive environment for your potential consumers.
2. Eliminates legal risks related to accessibility
3. Enhanced overall user experience
4. Improved search engine optimization (SEO) resulting in more exposure.

To meet Section 508 compliance requirements, your website, service or product must meet WCAG version 2.0 Level A, AA success criteria at minimum. If you have taken a step ahead to already adopted WCAG 2.1 – a round of applause for you. 
WCAG 2.1 is compatible with 2.0 which means that your products which are conformant with 2.1 standards automatically comply with 2.0 to help with compliance.
A good place to start with checking for compliance, will be with an Accessibility Audit of your digital product or service. 

The possible risks of not being compliant with Section 508:
1. Accessibility non-compliance lawsuits
2. Losing potential customers
3. Inadequate user experience
4. Defamation of brand name
5. Decreased search presence