I've seen teams spend £150 million and get nowhere near the Champions League. It has taken Manchester City a billion to get there. There are no guarantees.
I did think there were one or two referees who had a personal thing against me. It wasn't them versus Celtic - it was them against me! I just think they wanted to take me on.
All the really good players I know, they all knew right from wrong. So many of them don't learn that at home nowadays.
Do I miss football in Scotland? It keeps you really alive, that's for sure. Your heartbeat fluctuates. I'm flatlining at the moment which is actually quite nice but you need to go up and down to stay alive.
It took me 35 years of being involved at a decent level of football to become manager at a great club like Celtic.
Fitness is a curve. You can be Lance Armstrong, or you can be really out of shape at the opposite end. People enter the curve wherever they are and then they can move up the curve, by better nutrition and better exercise.
Are there Martians out there? I haven't got a clue. Is there life out there? I have no idea.
I think if you've managed Celtic or Rangers you can go on to be Prime Minister of Great Britain, it's that hard.
I'm a better coach now than when I joined Celtic. The longer you stay in any job, the better you become. If you lose your drive, your enthusiasm, your imagination, that experience is no good.
Everybody at Barcelona loves Messi. They can't speak highly of him.
You people sometimes are like those serial killers you see in films who cut out the words 'I am going to get you' or 'your wife is next'.
I think what I've actually achieved as a manager does sometimes get a bit overlooked, because all people think about is the media side of things. They tend to forget I've not done so bad.
I've been in football a long time and people have problems through debt, drugs, drink and family.
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