An impact driver makes the most sense when resistance is the problem.
Imagine driving a long structural screw deep into timber. As resistance increases, an impact driver's hammer-and-anvil mechanism begins producing repeated rotational impacts. This helps keep the screw moving without relying only on continuous motor torque.
For deck building, framing and repetitive structural fastening, that is a real advantage.
But a cabinet hinge, furniture connector or small bracket is a different job.
There, the question is often not:
“Can the tool turn this screw?”
It is:
“Can I stop before I damage the screw or material?”
That is why screwdriving control matters in everyday DIY.
ST3 separates this operation into a dedicated Screwdriving Mode of 0–500 RPM, with an electronic clutch and electronic torque levels.
Instead of simply delivering as much torque as possible, the user can choose a more appropriate output for the fastener and material.
That makes more sense for furniture, cabinets, fixtures and other jobs where overdriving is a common problem.