The 52-year-old was confirmed as head coach for next year's tour of New Zealand today.
It will be Gatland's second spell in charge having guided the team to victory in Australia in 2013 - their first series win for 16 years.
"If there's people who believe there's no chance of us winning there, then don't get on the plane," Gatland said in a press conference. "We've got to believe we can be successful. Everyone wants to be involved at the highest level and that's the most important thing about this for me, to challenge myself against the best.
"You want confident players to go down there and play in an incredibly tough environment. One of the challenges is putting together a team of people. There will be players who are used to being number one at their clubs and country, but now they might be number two or three.
"You want good, positive people, in terms of how they handle disappointment. The makeup of the personalities is very important."
The tour will be held from June 3 to July 8 in 2017.