I'm not a fan of the flavour of food cooked in a slow cooker. I feel like it has a specific quality to it. Like, I can tell it is slow cooked, and everything loses its definition of flavour. If I cook a stew in a dutch oven the carrots still taste like carrots, but in a slow cooker the carrots kind of taste like the rest of the stew in a vague way.
I don't know how to describe it but there is definitely a noticeable "slow cooker flavour"