The problem in accessing a website which one user faces would not be the same as another user faces. From user to user the conditions change, requirements change, challenges differ, and hence, accessibility options and requirements also change. Therefore, the website accessibility issues are of different types and different types of users report different issues. Every issue must be taken into account to improve the visibility, usability, and overall user experience of the website. A simple breakdown of some of the most common site accessibility issues would tell you the thing you may have to think while getting the site designed.
Some users may face the challenge of poor vision while some may face the challenge of color blindness. Some may find the website poorly adjusting to the screen size and resolution thereby affecting visibility and operability both. Color contrast issues, content that does not get resized for optimal reading, hidden, insufficient, or unavailable descriptions for audios, images and videos, and so many other problems loom over a webpage. These all demand rectifications.
Users with limited mobility or challenge would love to get far more control on the website accessibility and operability through keyboard controls, and labeled descriptions of controls. Rectification of input errors should be simplified, and also the information input method must be made easier. Many input devices like head wands and mouth sticks when supported by a website for data input, helps people with challenged motor skills a lot. Also, easy swapping between the input devices helps a lot.
Users get impacted by auditory challenges and then they need the help of textual content to identify and understand what is in a video or audio file. That is why such guidelines add to the accessibility of the site content. A site must have captions and descriptions with any such file which an auditory impaired person may access.
Cognitive challenges affect many users. Some users read but cannot interpret easily. Some have difficulty understanding things textually while some understand things textually better than images. Many remember it now and forget soon and have to come back to the site again sooner or later to refer to the information, hence for such user navigation through the site must be totally fluid and easy. Too many comments, too much of visual effect, too many distractions can be a problem with many users. Hence you must realize when the effects, graphics, promotions, ads, etc. are getting too much overwhelming for the senses.
Overall, neither the site should be stimulating senses too hard to overwhelm the person, nor should the site have too limited data that users can barely interpret things when they are challenged in some way. When such things are noted along with feedback from real-time organic users and also from sophisticated analytical tools and software, then you can get a complete idea of how much access the site is and how you should proceed with rectifications and improvements in it.