Which of the following is a reason a lift may be disallowed?

A lift may be disallowed if the lifter did not follow the correct commands during the attempt. In powerlifting, judges expect lifters to adhere to specific commands given during the lift, such as when to start, pause, or finish the lift. Not following these commands could result in immediate disqualification of the lift, as proper execution and adherence to regulations are crucial for maintaining the integrity of the sport. This ensures that all lifters are judged under the same rules and conditions, providing a fair environment for all competitors.

The other options do not directly pertain to reasons for disallowing a lift. For instance, attempting a minimum weight is not a requirement for a valid lift, so not meeting this could not be grounds for disqualification. Similarly, completing a lift without failures is an indication that the lift was successful, and lifting less than a personal record does not affect the validity of the lift according to the rules, so these factors would not lead to a lift being disallowed.