The big question this week is not whether Lance Armstrong cheated (we know he did) but why he has decided to admit it now.

Armstrong has spent well over a decade vehemently denying he used performance-enhancing drugs, and has stayed almost totally silent since the USADA decision last fall that concluded he perpetrated the biggest doping scandal professional sports has ever seen.

So why confess, even in a limited way, to Oprah Winfrey now?

The short answer is money.

It’s been reported that Armstrong is keen to have his lifetime ban relaxed so he can compete in elite triathlons, which are sanctioned by the World Anti-Doping Code. Usually the stated motive for this has been, "Lance is driven to compete" and "he can’t live without competing against others at the highest level" or some variation on that.

But a report in the Wall Street Journal mentions an unnamed source who says Armstrong sees competing in triathlons as his most reliable source of future income.

This makes a lot more sense.

Armstrong’s net worth is estimated to be more than $100 million US. However, never has that fortune been less secure than it is now. He is facing a barrage of lawsuits that could cost him tens of millions of dollars in all.

The big one is the whistleblower lawsuit launched by his former teammate Floyd Landis. The suit alleges that Armstrong effectively defrauded the U.S. government, because the U.S. Postal Service was the title sponsor of his cycling team. The contract specified the team's riders could not use performance enhancing drugs. Since Armstrong was part owner of the team, he could be on the hook for a substantial part of the estimated $50 million the U.S. Postal Service paid to be the main sponsor.

The U.S. Justice Department is now considering whether to join the lawsuit, and is expected to announce its decision Thursday. If it does, many believe that will greatly increase the chance of the suit succeeding.

Income sources dried up

If all this wasn’t enough, there is another, possibly even bigger, financial problem. At just 41 years of age, Armstrong is virtually unemployable. Since he was a teenager, all he’s done is be an athlete. Since he recovered from cancer in 1998, all he’s done is be a professional cyclist. Sure, many other pro cyclists face an uncertain future when they retire, but they don’t have lifetime bans restricting them. Most quit the sport with their reputations intact, and go on to be coaches, team managers, or bike manufacturers.

The daunting question facing Armstrong right now is: what’s he going to do for the rest of his life? How is he supposed to work if he is banned from sport? At the moment, he can’t earn prize money or appearance fees at high-level competitions. And if he can’t compete, then he won’t convince any company to sign an endorsement deal. Under the ban, he’s not even allowed to coach.

Aside from writing another book, he appears to have no way to make any money.

Armstrong’s current net worth is substantial, but the lawsuits put some or all of that money at risk of disappearing. At best, his financial future is uncertain. At worst, he’s staring at a potentially catastrophic situation.

The Oprah interview is the start of the campaign to avoid that. If he can get his lifetime ban from sport lifted, everything changes for him.

Make no mistake, Armstrong still has many, many devoted supporters, who would love to see him race again, whether that’s in a triathlon, marathon or something else. Maybe he could even convince a company to endorse him post-redemption. If he is again allowed to compete at a high level, he can restore his ability to earn money.

If he can’t get the ban lifted, then his future looks increasingly bleak.

David Michael Lamb is a senior producer of CBC Radio’s World Report.