Elm complier confusing error?

gistfile1.md

I have the following model and update function:

type alias Model =
  { people: List String
  , entry: String
  }

model : Model
model =
  { people = ["foo2"]
  , entry = "foo"
  }
  
update : Msg -> Model -> Model
update msg model =
  case msg of
    AddNewParticipant ->
      { model | people = List.append model.people model.entry }

On line 19, we see:

      { model | people = List.append model.people model.entry }

Elm complier gives the error:

-- TYPE MISMATCH ------------------------------------------------------- app.elm

The type annotation for `update` does not match its definition.

41| update : Msg -> Model -> Model
             ^^^^^^^^^^^^^^^^^^^^^
The type annotation is saying:

    Msg -> { ..., entry : String } -> { ..., entry : String }

But I am inferring that the definition has this type:

    Msg -> { ..., entry : List String } -> { ..., entry : List String }

The real problem is that I'm passing a String to the List.append function.

      { model | people = List.append model.people model.entry }

should be

      { model | people = List.append model.people [model.entry] }

So why isn't the compiler telling me that the problem is with List.append? Telling me the problem is with update is confusing.