What is sandbagging?

I've been asked, "What is sandbagging?"

Sandbagging: In games and adversarial settings, to "sandbag" is to intentionally understate one's strength, with the intention of deceiving one's opponents into overreaching. The sandbagger can then reveal a hidden strength to take the opponent by surprise.

Sandbagging is the practice of deceptively portraying oneself as being in a weaker position than is true.

• In drag racing, when a racer has a dial-in time much slower than the car can actually perform. The function of sandbagging is to guarantee a win by outperforming the slower opponent at first, and then hitting the brakes near the finish line in time to just barely beat the opponent.
• In a Demolition Derby, sandbagging is avoiding contact with other cars, drivers refuse to be aggressive and/or pretend to have mechanical problems until the last two or three cars are running then their car will start running just fine and/or they become more aggressive; or hitting weakly to ensure better odds of surviving and winning the derby.
• In poker, in which a player with a strong hand bets small amounts to convince opponents to stay in the game.
• In golf, a "sandbagger" would enter a tournament, claiming a higher golf handicap than real, to gain an advantage in the tournament and over other players.
• On Internet chess sites, sandbagging is the malevolent resignement of a chess game in order to add "Elo" points to a partner or to a second user account.
• In the sales environment, sandbagging is holding aside completed sales with the expectation of producing them at a specific time of the week or month when there might be extra incentive or higher commissions. (also called "Stuffing the channel")
• In CB radio slang, "sandbagging" is listening in on others without talking or making one’s presence known, for entertainment or for collection of information on others.
• In the rock climbing world 'Sandbagging' refers to giving a climb an easier grade then it deserves. An example is a climb that would typically be rated as 5.10+ being rated as 5.9- (YDS).
• In Bowling, "sandbagging" is lowering your average on purpose, in order to gain added pins of handicap.
• In Weight lifting, "Voltaire is always sandbagging at the gym. He says that's all the weight he can lift but we know the truth... dirty sandbagger."
• In law, to refer to the process of concealing winning arguments for as long as possible, to prevent the opposing attorney from preparing effectively to counter them.
• In Business accounting, overstating the value of the company to encourage others to invest.
• In customer service, delays returning a phone call to a complaining customer, hoping the customer gives up. "Not my job", "my boss is out"
• Waiting for payment? "it's in the mail."
  

Mark Twain once said, “There are three kinds of lies: Lies, damn lies and statistics.”
Even when statistics don’t lie, they can be very deceiving.

Ancient usage of the word, "Sandbag" can refer to a crude weapon consisting of a small bag filled with sand for use as a cudgel typically by criminals, or to the act of striking a person on the head with such a weapon. This usage is obsolescent in normal speech, appearing mainly in legal codes.

Ever been sandbagged?
Tell me how.

Please read my book, "Confessions of a Sandbagger"