The lowering phase of a lift matters more than most people train it

The eccentric portion of a rep builds strength and size through a different mechanism than lifting the weight

Most lifters focus their effort on the concentric (lifting) part of a rep and let the eccentric (lowering) phase happen almost as an afterthought. That's leaving something on the table: the eccentric phase, where the muscle lengthens under load, can generate more force than the muscle can produce concentrically, and it causes a distinct pattern of muscle damage that's strongly linked to hypertrophy signaling - which is part of why a controlled, slower lowering phase tends to produce more soreness and, over time, more growth than a rushed one.

Eccentric-focused training is also one of the most effective tools for building tendon and connective tissue resilience, and it's used clinically to rehab certain tendon injuries (like Achilles tendinopathy) precisely because tendons respond especially well to controlled eccentric loading. Slowing the lowering phase to around 2-4 seconds, rather than just dropping the weight down, is a low-effort way to capture more of this benefit on any exercise.

This doesn't mean grinding out extremely slow eccentrics on every set - that adds significant fatigue and isn't necessary for most goals. But letting the weight simply fall on the way down wastes a meaningful part of the exercise's potential, especially for anyone chasing muscle growth or trying to bulletproof a previously cranky joint.