However, the current year has not been so kind to the former Neath scrum-half.
A loss of form had seen the critics call for his exclusion from Ian McGeechan's touring party but fortunately for Williams, and for his army of fans, his name was among five wingers read out by tour manager Gerald Davies on Tuesday afternoon.
"There was a lot of competition to get on the tour and I never for one minute assumed I was going - that hadn't changed from day one," said Williams, who first toured with the Lions in New Zealand four years ago.
"The 24 hours before the announcement was nerve-wrecking and it was a huge relief to hear my name read out."
Now that his place on the plane to South Africa has been assured, Williams is determined to prove his doubters wrong by recapturing the form that saw him recognized as the planet's best player.
"It's not been a great couple of weeks for me with all the criticism I've been receiving but now I want to go over to South Africa and prove people wrong.
"Of course, this year has been difficult because expectations on me have been higher - and the criticism has certainly increased.
"I try not to worry about it as I put enough pressure on myself but I don't think I'm playing too badly.
"The easy part of being selected for the tour is out of the way but there's still a couple of important weeks left in the season. The pressure is off a little but I need to repay the faith that the selectors have put in me.
"Now I want to play my best rugby and hit form at the right time. I'm more determined than ever to do that on the tour because I know I'm capable of it."
Williams has already impressed once in South Africa when he outshone previous IRB World Player of the Year Bryan Habana during Wales' 2008 summer tour.
Now the 5"8 star is looking for a similar level of performance this time around, especially after being on the receiving end of a crushing series defeat during his only previous experience as a Lion.
"2005 wasn't a great Lions tour because of the results but I really enjoyed the experience and felt I came back as a better player," added Williams, who featured in just the second Test against the All Blacks in Wellington four years ago.
"I wasn't really involved in the Test series but this time I want to play in every match. I've loved my battles with Bryan (Habana) in the past but it's not just about us.
"I enjoy playing in South Africa. I enjoy playing at altitude and on the running surfaces - that's where I play my best rugby.
"It's a great place to play and I've scored a few tries against them. I want that to continue but I need to finish the season strongly by enjoying my rugby, then train and play well with the Lions."
