A lock-in is where each party hands an agreed to portion of the wager to a 3rd party to hold. If one of the participants doesn't show, or backs out, the other participant gets the lock-in money for actually doing what they said.
Example: $1000 run, $200 lock-in. Both parties give $200 each to a 3rd person to hold. Person A shows up (or doesn't show up at all), but then backs out of the race. Person B gets his $200 back, plus the lock-in money from Person A.
Agreeing to a race over the phone without handing lock-in money to a 3rd part is not locked-in. Either party could back out right now, with no financial consequences.
This is Grudge Racing 101.
