Direct answer: Training until failure means reaching the point where you cannot complete another repetition in the set pattern. This does not need to happen in every sets. The choice depends on exercise, experience, safety and recovery.
Distinguishing loss of control effort
A difficult sets can end before failure and still be part of a useful program. When the position changes a lot, you may have reached a technical limit before a muscle limit. Trying to continue anyway should not be treated as a dedication requirement.
Consider the equipment
Failure on a machine with supports and limits may have different consequences of failing under a free bar. Learn locks, supports and how to end the exercise. Do not look for this limit without knowing the operation of the equipment and the safety guidelines of the site.
Evaluate the cost for the rest of the training
A sets pushed to the limit can reduce the performance in the following. The coach needs to consider this effect when organizing volume and rest. If you lose execution and performance too early, it is worth reviewing the effort distribution rather than insisting on the same pattern.
What to record and discuss
- Confirm the effort planned for each exercise.
- Learn to close the sets safely.
- Register how performance changes in the following sets.
Questions about this topic
Is a no-fail sets useless?
Is technical and muscular failure the same?
References and further reading
Educational content. Examples need adaptation to your experience, routine and health context.