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here are some wet sanding examples using 600 grit.



This needs more sanding. Use the sanding step between coats to create a smooth and uniform surface. It's clear that there is some texture in that paint that you don't want when you are done. Knock that down with 400 - 600 grit wet before you go on to the next coat.

The reason people do two coats before sanding is to reduce the amount of wetsanding (which most people hate.) Personally I would at least scuff lightly with red scotchbrite after the odd numbered coats and wetsand after the even numbered coats.

I don't like to apply paint to any shiny surface unless it's still slightly tacky from the previous coat. If it's dry enough to scuff (wet or dry) then scuff it.