Pain of being left behind in 2015 drove Kilcoyne on to stamp passport this time
Every morning when Dave Kilcoyne wakes up, the first thing he sees are the words 'Try and get better every day'.
Written on his bedroom wall, it's a constant reminder of the relentless pursuit of success which in recent years has become even more intense.
Four years ago, Kilcoyne was overlooked for Ireland's World Cup squad in favour of Jack McGrath, who then went on to play in all three Lions Tests on the 2017 tour of New Zealand.
Back then, the odds on Kilcoyne making the plane to Japan would have been slim, but such have been the impressive improvements in his all-round game, he has timed his run perfectly to usurp McGrath.
Of all the Ireland players in pre-season, Kilcoyne made huge ground in terms of cementing his place, particularly after his barnstorming display in Cardiff.
The 30-year-old looks fitter, sharper and more robust than ever, which, in turn, offers Joe Schmidt another explosive option from the bench.
Kilcoyne has come a long way since having his World Cup dream crushed in 2015, but without that painful experience he knows he might not have transformed his own game enough to become an even better player.
"That was a massive driver for me, yeah," he admitted. "After getting that phone call, I remember having a chat with my brother Alan and saying, 'I'm going to be on that plane in four years'.
"That was one of the texts that we had between each other. He said he remembered being in my house after I didn't make it and that he was so proud that I did make it this time.
"As your career progresses, you get limited opportunities to play in a World Cup, so I wanted to make sure I left no stone unturned. There wasn't a whole lot to turn around. It was quite a close call at the time. But I think I looked more towards myself rather than the coaches.
"I looked at areas in my game that I could improve. I have that written in my room at home - 'Try and get better every day'. That's what I try and do."
The loosehead's parents Pat and Pauline have been with him every step of the way.
"I'm a big family man, my parents have been with me through thick and thin, and my two brothers," Kilcoyne said.
"They've been there for me, not so much a shoulder to cry on but they feel the hurt as well."