Why are some Cura settings in yellow?

I sometimes see a Cura setting highlighted in yellow but I can’t find an explanation.
Does anyone know why some settings get highlighted in yellow?

Thx,
t
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I look at it like this:

Caution - May give undesired results - rough surfaces, sparse infill, very visible layers and the like.
Error - Will give bad results - Open holes, out of tolerance dimensions, etc.

Thanks!
Hadn’t seen the red case but good to know :wink:

If you ever see one in plaid, start running away quickly…