"I wouldn't say I was the best manager in the business. But I was in the top one".
That's a quote from the late Brian Clough. And it's fair to say that Cloughie did not lack confidence, and that's what made him such a successful manager, particularly during his time as Nottingham Forest manager.
"If you don't feel confident yourself, you can't possibly spread confidence to your players". Another quote from Clough, yet one that goes without saying.
A heightened sense of confidence can drift into arrogance and brashness. How one displays it and the results that follow marks many out.
Daniel Wiffen's rise through the swimming ranks certainly marked him out and he has the confidence to go with it.
On the day Team Ireland confirmed the 12 swimmers for the Paris Olympics, Wiffen was in good form as he spoke to the media, relishing what might transpire in the French capital.
"I'd say it's the pinnacle of our sport," he said.
"Olympic gold is the highest achievement I could ever win. It's just like the best thing in any sport I would say."
And clearly Wiffen wants to be the best. He's achieved a lot so far.
He served notice to everyone on 10 December of last year when he became the first Irish swimmer to set a new world record, shaving 2.96 seconds off Grant Hackett's time in the 800m freestyle short-course.
Prior to that he won gold in the 1500m freestyle at the European U-23 Championships in Dublin along with silver in the 800m and 400m events.
With expectations duly raised, Wiffen smashed them at last February's World Championships in Doha, when he claimed gold in the 1500m and 800m freestyle and walked off with the best male swimmer award from the event.
And now Paris beckons, where Wiffen, who turns 23 on 14 July, will compete in the 800m freestyle, 1500m freestyle and open-water 10km events.
When asked what separates him from others, he replied: "I'd say it's definitely the mindset. I think everything in sport is to do with the mentality and I think I've probably got one of the best mentalities in the sport, in most sports to be honest.
"I feel like I always want to win, I will never back down from a fight and that's what I'm bringing into this Games. It's just going to be digging in hard and really grinding my teeth out in the middle of that 1500m.
"I definitely don't lack confidence. I've been told multiple times that I'm a most confident person. When I was younger I was definitely confident and that has grown as I have got faster."
With success comes greater attention and that was certainly the case after winning those World medals.
Still, Wiffen's focus quickly turned to Paris after his success in Doha.
"Has my life changed? I've probably got a lot more sponsors, which has definitely helped me.
"I'd say I've definitely got a lot more attention. And also, I think it's actually made me train harder. Which I would say a lot of world champions would not say.
"Normally when you become a world champion, or what I've seen from the world champions that I’ve trained with in the past, they kind of slack off a bit. As soon as they reach that level. Not me.
"I kind of decided that World Championships doesn't mean that much this season. I was like, 'I may be world champion but that's not my goal for this season’. That was just a stepping stone to the Olympics.
"As soon as I hit World Championships I took a couple days off and just put my head down.
"And then obviously the sponsors were great. I've got so many new sponsors, which helped me contribute to my training this year that allowed me to go on so many different camps - allowed me to say that I'm in the best shape of my life for going to this Olympics."
Wiffen will also make history in Paris when he competes as Ireland's first Olympian in the open water 10km marathon on the River Seine.
A case of nothing ventured, nothing gained, it would seem for the Loughborough University student.
"The 10k of the marathon swimming is on 9 August so it's like four or five days after I finish in the pool. I mean I'm doing it just for a bit of fun maybe. You can qualify for the 10k in the pool if you can get the Olympic qualifying time in the 800 or 1500 so I qualify and, since we don't have any open-water swimmers in Ireland, I thought why not have the opportunity.
"I train like an open-water swimmer so I'll just put my hand in there and see if I can get something out of it.
" I never go into a race without the attitude of trying to win it so my goal obviously is to try to come out with a medal. It would be amazing, I would probably be the first person ever to do the open-water with my first race at the Olympics and win it.
"I'm going in to see how the race pans out. It's an hour and 45 minutes race so it will be the longest straight swim I've ever done in open water. My training partners are in it so we've actually got a crowd of people from Loughborough who are going to be in the race. I'm looking forward to it and the bonus is you get to swim in front of the Eiffel Tower which will be good."
As for concerns about fatigue, Wiffen added: "Maybe there will be a bit of fatigue. Hopefully I will have a couple of medals, I don't know, we'll see, and that will probably boost my morale going into the open water. We'll see what happens."
Wiffen's rate of progression has been remarkable. He lays out the improvement, when saying: "Since I started in Loughborough I've dropped 16 seconds in my 1,500 every single year, so it's literally been a straight-line progression for three years in a row, which I've kept on for this year."
And in this Olympic year, it's no surprise then for the double World Champion to have the testers calling at his door more often.
"I think this year especially it's definitely been a prominent thing in training. I think I've been tested — I need to actually count how many times — but it's over 20 since January.
"I would like to say that I'm probably one of the most tested athletes in the world right now.
"I'm not really surprised when you have the results that I've had and the time progressions. I hope everybody gets tested the same as I do. I'd like to say that's the case, but I don't know."
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