Sometimes they don't. It depends on the code,and where the space is. It is fairly well documented in this forum that a trailing space after a closing php block can cause errors (particularly 'Headers already sent' errors), so it seemed possible/likely that the trailing space after the error reporting block at the beginning of your page was preventing error reporting from writing the original error(s) to the page.
What happens if you remove the trailing space then upload and access your page?