"I was a little lucky because at home my parents used to play around in the stock market and I thought this was an interesting thing. So at 13 I started to buy stocks and I was protected by total ignorance, but I just kept going until I started to understand some things and that took me a long time," Neilson says.
From those early beginnings he has gone on to build one of the most respected and recognised boutique funds management houses.
In fact, Neilson rates putting together the team currently running Platinum as one of his most significant achievements.
"What we've done well here at Platinum is inculcate our philosophy into a whole group of people and I think that's what may be considered as valuable, instilling them with an understanding of a process to analyse and address markets," he says.
According to Neilson, the evolution of the financial planning industry is the sector's high point so far.
"The financial planning industry has changed a lot in its degree of commitment and seriousness. Fifteen years ago that was not the case. There were many participants who saw it as a transient activity. Now I think it's become much more of a profession. I think that's the big change and that's a great credit to the planning organisations and a great help to the public receiving their advice," he says.
At the same time, short-term trends in the industry are something Neilson identifies as a low point.
"Periodic fashions are a low light, where you talk in terms of structured products and ETFs (exchange-traded funds), and in the end you have to ask: 'Will the client be better off with those structures or not?' In many cases there is only one person making money out of that deal and it's not the client," he says.
"So I think the low point comes from when we lose sight of our ultimate lord, which is the client."
One development Neilson wishes he could change is the use of gearing strategies among investors, mainly because individuals are never able to cope with the downside of these processes.
"Most people think they are prepared to take the losses when they come, but they're actually not. They fall apart, they lose their judgment, and they close out positions because they've got too deep into it. I'd like to limit that if I could," he says.
Looking toward the future, Neilson believes scale in the funds management space will take on great significance. He also predicts structured products will again become fashionable from time to time.
But the big issue he sees for the industry as a whole is pricing in regard to what individuals will be willing to pay to achieve a particular result.
"The big threat to the industry is paying for skill. In the advisory area will people be prepared to pay fully for the advice they get and in the funds management area will good fund managers be able to charge the fees they feel are reasonable? These will be constant bones of contention," he says.
