One common problem on many web pages on input forms where the input is a number is that they only allow you to input a number from some predefined list. For example, you might want to find laptops between $434 and $537 but can’t – you have to resort to between $400 and $600 because you cant input your own numbers. Or maybe you wanted to view 36 articles (or posts) per page rather than 10, 25 or 100. But you can’t. Not because it would be difficult to design or program, but because of the incompetence of web developers.
There is no excuse for this sort of action. I firmly believe that the reasoning behind it is that the designers think “well there’s not much difference from $434 and $400 so it doesn’t matter”, basically referring to the just noticeable difference. But in a later post I will entirely demolish the concept of just noticeable difference with a rigorous mathematical proof denying it any chance of existence.
And this is how it should be: