What must occur for a lifter to be awarded a personal best?

For a lifter to be awarded a personal best, they must lift a weight that they have not previously lifted in competition. This definition is crucial as personal records are specifically measured against an athlete's past performances. Achieving a new personal best reflects growth and improvement in the lifter's strength and skill, which is a significant aspect of competitive powerlifting.

The other choices do not accurately define what constitutes a personal best. Having the highest score in a weight class is indicative of overall performance in that event but does not necessarily correlate with personal growth; it’s possible for a lifter to have the highest score while still not exceeding their previous personal best. Successfully completing all attempts refers to overall performance consistency but again does not alone define an improvement measure. Lastly, achieving the maximum allowed weight for their category speaks to limits set by competition rules rather than individual progress. It's important to note that a personal best is solely based on surpassing one's own prior performances, making the understanding of personal bests vital for both lifters and their coaches in tracking progress and setting goals.