To make his name in the early days he started performing concert tours in England six nights a week, every week, for months on end. He said yes to every request, answered every phone call, visited every fan in hospital, and completely wore himself out.
"It really was too much. I was the type of person who just couldn't say no," O'Donnell says.
" I could see that all my hard work was yielding results but eventually, the pressure of all the commitments began to take its toll on my health. I was near to cracking up from doing too much work. It was literally too much. I kept saying yes, yes, yes, to everything. At the end of the day, the human body can only take so much."
Over a period of two years in the early 1990s Daniel took time to recuperate and assess his achievements. He loved to perform - his career was never about making money, he says - and eventually his delight in what he did returned when he gave a hugely successful concert at the Point in Dublin that took his career to the stadium level where it has remained.
But despite all the gold records and the accolades, he has kept faith with his hometown and his heritage. "They'd be very quick to cut you down if you walked with too much of a spring in your step around Kincasslagh. That's what keeps me grounded," he says.
O'Donnell still lives in the tiny village he grew up in, and the award that means the most to him is the one presented by his home county.
Says O'Donnell, "The award I hold dearest to my heart is the Donegal Person of the Year. It honors me as a person from Donegal.
"I love Donegal more than anywhere else in the world. That and my fans are the reason that I do what I do - and that I enjoy it as much. I have a charmed life."
For details about O'Donnell's U.S. tour, visit www.daniel-site.com/tour-dates/