They do not tend to factor in that their odds don't change - that they are dealing with luck and, in the case of Gatland, he's going to have to ask whether he can honestly expect victories on this tour if the Lions continue to offer what they have.
He might also be kidding himself, if he thinks there won't be a significant jump from playing Super Rugby teams to taking on the All Blacks.
"We put ourselves in position to win the game and we can take a lot of positives from that," said Gatland. "Saturday will be another tough encounter, so I expect to see an improvement.
"There is so much strength in depth in this country, I don't think there will be a lot of difference between some of the Super Rugby sides and the All Blacks."
After seeing his side lose 22-16 to the Blues, he talked of the improvements he saw and his confidence that there will be more steps in the right direction this Saturday.
But unless the Lions are willing to take some more risks, throw the occasional offload or run from deep if they think it is on, Gatland is kidding himself in the same way as the gambler who keeps putting it all on black.
The Lions are big, strong, physical and they can scrummage - or at least some of them can - and organise a good lineout. But their game plan is crying out for something more.
If they don't offer it, their only chance of winning is luck going their way.
"We know the quality of New Zealand sides. I thought it was a big improvement from Saturday and we will continue to improve.
"The try at halftime was obviously disappointing. Let's take nothing away from Ihaia West and the offloading of New Zealand teams, and that is only going to continue.
"It was a moment of magic that you do get from New Zealand teams. The thing about playing these quality sides is that you learn a lot.
"If you go back to 2013, we won the first game by 70, the second by 60 and it wasn't great preparation for the tests."
