i just realized that i sounded like a dick, which wasnt quite what i was going for at all...
anyway i was writing a paper at the time of the response so i didnt have time to write a more elaborate answer. the thing is, depending on the key and scale that you're using you might find yourself using the 23-24 frets a lot or not at all. if you're playing in the key of E minor (assuming you're tuned to standard) you might not have an absolute need for the 24th fret as you can reach that note by bending the 22nd, in this case you wont really use the 23rd fret at all. but if you're playing lets say in F minor, then that 24th would come in really handy.
Theres a really simple way of putting it without sounding like an ass.
edit: yay post 500!! i've been here for over three years and just now im at 500...i need to post more often