Russian President Vladimir Putin, who has launched a full-scale vicious invasion of Ukraine, stopped socialising aged 11 after setting himself a serious goal.
Born into a working-class Saint Petersburg family, Putin himself admitted that he was badly-behaved "hooligan" as a youngster.
In an interview appearing in his 2000 book, ' First Person ', one of his teachers, Vera Gurevich said Putin "abruptly changed" when he was 11-years-old.
She told the book: "[Putin] himself changed very abruptly in the sixth grade. It was obvious he had set himself a goal.
"More likely he had understood that he had to achieve something in his life."
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Before this, a fellow teacher told Vera that she regarded Putin as "sneaky and disorganised" but Gurevich said she immediately spotted that he would "make something of himself."
In the book, Putin said he enjoyed school "as long as he managed to be the unspoken leader," meaning he didn't try to command people and remained "independent."
But he realised that he needed to improve his social status - and began playing sports, alongside trying harder in his classes.
Vera helped Putin improve, as she began to shower him with attention and discourage him from hanging around the streets with a wayward pair of brothers.
But while other pupils enjoyed attending dances, Putin avoided attending and "didn't like socialising" in favour of attending judo classes four times a week.
He told the book's authors: "When I began to do sports...I used to work out every other day and then every day.
"Soon I had no time for anything else. I had other priorities, I had to prove myself in sports, achieve something, I set goals."
The pair grew very close, with Vera becoming a second mother to him, even taking him on holiday.
She told the book's authors in 2000: "I think [Putin] is a good person. But he never forgives people who betray him or are mean to him."
In an interview with the BBC today Defence Secretary Ben Wallace said it was clear President Vladimir Putin was a “spent force”.
He said the Russian leader would not break the people of Ukraine and that he now potentially faced decades of occupation which would be impossible to sustain.
“Whatever we think about President Putin, he is done. He is a spent force in the world. No-one will be taking his phone calls in the long term,” he told BBC Radio 4’s Today programme.
“He has exhausted his army, he is responsible for thousands of Russian soldiers being killed, responsible for innocent people being killed, civilians being killed in Ukraine.
“He is reducing his economy to zero, because the international community has decided that is absolutely unacceptable, what he’s done.
“So he is a spent force in the world and I don’t know whether he thinks that’s a clever thing to be, but that diminishes his own country in the world and he has to take responsibility for that.”
