I played fretted for over thirty years without ever thinking about even trying fretless.
Then I got a gig, without any audition, with a band who, it turned out later, thought I did play fretless - no-one seems to know why they thought that.
I liked the band so I bought a lined fretless Fender Jazz and it turned out that I could play fretless at least well enough.
The Jazz got replaced by an unlined fretless Fender Precision which in turn was replaced by a Takamine B10 hollow bodied bass.
It also led me to an NS electric upright and then to a double bass, which, although I could get a tune out of it, did prove either beyond my ability or beyond my motivation or beyond both.
After eight years that band is no more and I am without any unfretted instrument.