* If it's easier to see with poor vision, it's also easier to see with normal vision / projected on a projector / over someone's shoulder on their screen / on a phone or tablet.
* Supporting screen-readers often makes it easier to scrape the site / app (not an 'average' use-case, I realize, and maybe even something the site / app owner wants to discourage) and to copy-paste.
* Supporting screen-readers also makes it easier to switch to 'text-only' or 'de-clutter' modes.
* Supporting (good) keyboard input can make things faster even for people with the option of using a mouse.
* Alt-text is useful if on a slow internet connection and images don't load, or even to describe an image you maybe didn't understand. It also usually gets copy-pasted out if you do a ctrl-a ctrl-c, so you have context of what images were shown where in the text.
* Video subtitles are useful for you to be able to choose to watch a video without sound.
* If your app / site can be used by someone with mental impairments, it's easier for all users.
Most web accessibility stuff does not involve adding disability-specific aid such as sign language, or braille, or ramps. For websites, you can get at least 50% of the way by just following the basic web standards, which I think is self-evidently beneficial.
Note: I am not arguing that the cost-benefit is necessarily in the company's best interest. I.e., I am not saying that including an accessibility feature is beneficial enough to the average user that it's worth the cost of development. I am merely claiming that adding an accessibility feature almost invariably does bring some benefit to other users. However, I will say I think that programmers and companies do routinely underestimate the benefits and overestimate the costs of actually developing these basic accessibility features.
* Supporting screen-readers often makes it easier to scrape the site / app (not an 'average' use-case, I realize, and maybe even something the site / app owner wants to discourage) and to copy-paste.
* Supporting screen-readers also makes it easier to switch to 'text-only' or 'de-clutter' modes.
* Supporting (good) keyboard input can make things faster even for people with the option of using a mouse.
* Alt-text is useful if on a slow internet connection and images don't load, or even to describe an image you maybe didn't understand. It also usually gets copy-pasted out if you do a ctrl-a ctrl-c, so you have context of what images were shown where in the text.
* Video subtitles are useful for you to be able to choose to watch a video without sound.
* If your app / site can be used by someone with mental impairments, it's easier for all users.
Most web accessibility stuff does not involve adding disability-specific aid such as sign language, or braille, or ramps. For websites, you can get at least 50% of the way by just following the basic web standards, which I think is self-evidently beneficial.
Note: I am not arguing that the cost-benefit is necessarily in the company's best interest. I.e., I am not saying that including an accessibility feature is beneficial enough to the average user that it's worth the cost of development. I am merely claiming that adding an accessibility feature almost invariably does bring some benefit to other users. However, I will say I think that programmers and companies do routinely underestimate the benefits and overestimate the costs of actually developing these basic accessibility features.