The NBA and NFL are fickle places. We forget that professional sports is more of a business than anything else, and the truth is that team owners love to manipulate our emotions for their profitability: they get citizens to support and pay for sports stadiums that their local governments can't afford, companies spend thousands on box seats that aren't worth very much and we drop hundreds in one night taking our family out to see a game. That's all fine and good.

There's the other angle of sports that might seem confusing to some, which is why a guy like Allen Iverson is still sitting around without a job. He's worked hard year in, year out and has been a productive player for most of his teams of the past, so many people are wondering why he's still sitting on the sidelines. Added to this list are other high quality, yet jobless, veterans in the NFL: Edgerrin James, Marvin Harrison and Derrick Brooks. All of these guys have been worth their weight in platinum as they've built amazing careers in professional sports. Here are a few reasons these guys might be not be playing this season or ever again.

1) We all get old. When a player gets an established name, its easy to believe that they are invincible. Many of us suffered through the last clumsy years of Michael Jordan's NBA career, and we've seen Shaq turn into a bloated shadow of himself. It breaks your heart, as we all once saw these athletes display nothing less than pure dominance. Many of the vets I've mentioned, including Iverson, are simply not young guys anymore (Allen is now 34). The problem is that they have the performance and salary expectations of superstars, pricing them out of most opportunities. An NBA athlete is nothing but a commodity to most teams, and human beings are a perishable commodity at that.

2) When it comes to pricing, everything is relative. People always wonder how great players are cut by their teams. Well, it's all a matter of the player's value relative to their price. If an All-Star is hired for $10 million dollars per year and gives an $8 million dollar performance, that individual needs to be cut from the team. Older NFL vets typically end up taking league minimum salaries and getting one-year contracts. The truth is that the value of an investment is not determined by the value of the commodity. A good investment is something with a price that is less than its intrinsic value.

3) It's the leadership stupid. Dr. Deborah Stroman, an expert on sports and leadership at The University of North Carolina at Chapel Hill, had this to say about unsigned free agents. "Money is only one aspect of a good veteran not being picked up by a team. The other factor is leadership. If the organization is trying to develop new leaders, the coach and/or general manager will not gamble the new leader's development and team chemistry with the introduction of a veteran leader."

4) Pro sports isn't what it's cracked up to be. I can't tell you how many NFL vets I've met who've entered their 40s with the bodies of old men. I wouldn't wish the life of an NFL player on my worst enemy, as the dreams of riches and power are slammed by the reality of pain killers, short contracts, financial insecurity and league minimums. Personally, if I were going into professional sports, I would enter the field as an agent or owner, not as an athlete.

5) Are you still worth the trouble? Dennis Rodman, once one of the most "interesting" characters in all of sports, never had trouble finding a new team because he was an amazing rebounder. Once Rodman got a little older, he went from being exceptional on the boards to being just "pretty good." Well, for all the trouble Rodman brought to the table, he was no longer worth the risk and unable to find a place to lay his sneakers.

When it comes to understanding sports, you have to understand business. Also, for every young black male with dreams of getting rich on the court, you might want to open a book instead. Getting paid for your mind is better than being paid for your muscle, because a person with a strong mind controls his own destiny.

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Dr. Boyce Watkins is a Distinguished Scholar with the Barbara Jordan Institute for Policy Research. To have Dr. Boyce commentary delivered directly to your email, please click here.