Had problem on producing geometry by scaled (and applied scale after) curve. I discovered (googled) that applying also changes “mean radius” of the curve. So final result of profile operation comes in an unexpected way.
Still looks good though. Generally, apply scales and rotation before using modifiers.
I sorted it out here in this final image. Situation was not releated to modifier. After scaling and applying it, if you use profile as “bevel object” the path remembers the pre-apply scale amount and gives it to “mean radius”. So it uses the profile according that mean radius. For example scaled path “0.5”. Applied. “Scale” shows 1 but “mean radius” shows 0.5. To be able to use profile in correct size we have to make “mean radius=1” . This happens when we scale the curve in object mode. And then apply.