The 33-year-old Welshman has impressed as Exeter have secured their first-ever place in the play-offs.
"It's just one of those things, for some people it happens and other people it doesn't, I'm pretty happy playing for the Chiefs," Welch told BBC Sport.
"I would have loved to have had a chance to play at the highest level, but if it's not meant to be, it's not meant to be."
Welch joined Exeter in 2012 from Scarlets and has been a regular starter for over three years at Sandy Park.
"I'm getting on a bit in years now and I think I'd probably be behind the pecking order from Phil Dollman in terms of the guys who missed out on their international call-ups," added Welch, who missed 12 weeks of this season after suffering a torn pectoral muscle.
Exeter boss Rob Baxter believes Welch's late start to his professional rugby career - he only began playing professionally a decade ago - could have contributed to his lack of a call-up.
"He probably started to get the frontline recognition in Wales relatively late, when you think of some of the players that broke through in Wales like Alun Wyn Jones, Luke Charteris and some of the other guys," Baxter said.
"There's been some stiff competition there and by moving out of Wales I think you do take yourself out of the international selection spotlight a little bit in Wales.
"The time he's played with us he's been fantastic.
"I've wondered really a few times about this, but I wonder whether in Wales they've looked at him and thought 'well that ship has sailed for him', probably a bit too early, and I think that's the case.
"With Damien, now age is probably against him, although physically he's still in great nick having come relatively late to rugby and having not played those years of frontline rugby that a lot of other guys have done when they get to his age."
Exeter lock Damien Welch has resigned himself to never playing for Wales.