Four reasons an LED strip won't dim all the way down
Minimum load is not met. A wall dimmer built for line voltage circuits usually publishes a minimum load. A short run behind a small driver can sit under that figure, and a dimmer below its minimum tends to misbehave at the bottom of its travel.
The driver's dimming range stops there. Dimmable drivers publish the range they follow. If the low end of that range sits above the level you want, the driver is doing what it was built to do, and nothing at the wall changes it.
The dimmer type and the driver do not match. Phase cut, low voltage PWM and analog control are different systems. A device speaking one language into a driver expecting another can track well at the top and fall apart near the bottom.
Low end trim is set high. Many control devices include an adjustable floor so the load never drops below a chosen level. It is easy to leave that where it sat on the bench.
Telling them apart without buying anything
Isolate the circuit before you open anything, and leave the wall box and any hardwired driver to a licensed electrician working to the maker's documentation, local code and NEC. Reaching a low end trim on a phase cut wall dimmer means opening a line voltage device, so that limit applies from the first step.
Start with the trim, since it costs nothing. Find out whether your control device has a low end adjustment and how to reach that (verify the trim procedure documented for that device before you attempt it). If turning the floor down moves the bottom of the range, you are finished.
If the run drops out, buzzes or steps rather than fading near the bottom, compare the connected wattage with the dimmer's published minimum load. A run under that figure explains itself. If the bottom is stable but higher than you want, read the driver's published dimming range instead. A driver that states where it stops has told you the answer, and the cure is a different driver.
If the behavior is erratic across the whole travel, treat it as a type mismatch and stop adjusting things.
What is worth changing, and what is not
Changing the tape is almost never the answer, because constant voltage strip follows whatever the driver hands it.
Where the driver sets the limit, one with a lower published floor is the real fix. The power supplies collection lists dimming behavior per item, and it helps to know what a non-dimmable unit is for: the EnoLED 24V ELD plug-in and direct-wire supply is non-dimmable by design and intended for switched runs, so no wall device will fade it (verify its published output and wattage first). On the dimmable side, the EnoLED 12V XRD phase cut dimmable J-box driver is one option for 12V tape run from a phase cut wall dimmer (verify its published dimming range, wattage and compatible dimmer types before you pair it with anything). Match the supply to the tape, 12V on 12V and 24V on 24V, and branch runs off the driver in parallel.
Where the control method sets the limit, dimming on the low voltage side of a fixed output supply changes which specification decides your floor. The controllers collection covers that route (verify the dimming range, load capacity and control protocol published for any unit before you commit).
One combination to avoid: a smart low voltage controller and a phase cut wall dimmer should not share a circuit unless the documentation for both explicitly permits it. Treat them as separate methods and pick one, then confirm the parts you choose against the manufacturers' own compatibility data.
