Snippet showing how `Async<'t>` always gets fully executed, so there's nothing like "completed Async instance". Took me a while to understand why there are no `Async.IsCompleted` or `Async.Result` properties like on Task

AsyncGotcha.fs

let rec retryForever (delay: TimeSpan) (workflow: Async<Result<_, _>>) = async {
    (*
        this always fully executes the `workflow` again,
        no result caching like Task's Result property
    *)
    let! result = workflow 
    match result with
    | Ok r ->
        return Ok r
    | Error _ ->
        do! Async.Sleep(int delay.TotalMilliseconds)
        return! retryForever delay workflow
}

let alwaysFail: Async<Result<unit, unit>> = async {
    printfn "Running"
    return Error ()
}

retryForever (TimeSpan.FromSeconds(1.)) alwaysFail |> Async.RunSynchronously