Is there a reason 1000 doesn't work with a < statement?

I have a raycast system for a player to be able to pick up a rigidbody only if its mass is less than, not less than or equal to a value. If that value is 1000 and the rigidbody's mass is 1000, you can still pick it up. If I change it to 999, and the rigidbody's mass to 999, you can't pick it up.

Is there any reason why 1000 doesn't work and 999 does? Cause if I have the pickup limit to 1000, if the rigidbody's mass is 1001 it also works insofar as you can't pick up said rigidbody.