Great first audition but after weeks of the live show he still looked and sounded like an amateur chimney-sweep in a talent contest.
He didn't have the X Factor, is the bottom line. Not in looks, personality, charisma and he sang the wrong songs and some of them out of key. Gary did not mentor him well in the song choice department and actually slagged him off for his vocal performance one week, that hardly helped.
You need an element of showmanship and variety - sadly this has been lacking amongst virtually all contestants this year except for Rylan, who in turn didn't have the 'chops' to win. Almost everyone else has done the same thing every week and what they do isn't original enough or at least as good as the original they are copying.