There was no outside pictures when I posted that why I missed a few.

I knew as soon as I saw the rot there had to be a step or something involved.
When I was an exterminator that was one of the first places I'd be looking for termites.
Makes it so much easyer for them to get in when someone builds a ladder for them with siding like that.
In addition there's mulch piled up againt the side of the house holding in moisture.
And that trim under the door sticks out past the threshold making a great place for water to take it's time to get under the door threshold. No amount of caulking is going to stop that.
I like to use 3/4 vinly lumber there with storm and ice shield behind it on the wall. That way it sits just behind the threshold, never needs painting.
What you want to bet there's also no sill pan or flashing under the door.
What a shame, once agin someone made it look pretty, but forgot water control 101.