When first starting b&w work, I didn’t intend to make landscapes. I wanted to concentrate on types of image that needed monochrome to work, and wasn’t at all sure that after years of working at colour landscapes I’d “see” a b&w opportunity. But I guess it just kind of happened.
When using film, I tended not to shoot the same scene in colour and in b&w, so most of my monochromes were a decisive choice in favour of b&w. that decision made before exposure. In general I was happy with the choices I made, and it was rare that I had any regrets afterwards.
Adopting digital cameras changed all this to a large extent since you don't commit to a colour or B&W execution until after you've made the exposure and had chance to think about it afterwards. I do still generally have a very clear conception of whether the photograph will be colour or b&w before exposure, But now I can change my opinion after the event, and sometimes - to my surprise - a photograph I expose thinking *colour* ends up as b&w. The reverse is a rare occurrence.