Submitting to solve question

[MedicRN]

Greetings,

I've been doing these for awhile now and am curious as to why you only get the 'submit' button when certain fields are filled in, i.e. if I solve it all the way down (vertically) I do not get the submit button...but if it's filled in across (horizontally) the submit button comes up. Either way, the puzzle is solved, but my time is longer if I have to cross-match the vertical with horizontal and fill in all those boxes too. Weird.