I came across this little trailer on a recent walk when I was expecting to be able to paint/sketch a landscape. I felt sorry for it and the air of abandonment which surrounded it.
It's a mistake to go on a painting outing with a preconceived idea of what you are going to paint. Sometimes it is necessary to get out of your comfort zone and try something a little different, or challenge yourself to new subject matter. It doesn't matter if your initial attempt is a little disappointing - at least you tried - and in the process new techniques may occur to you, or you may use a colour range you had not thought of before.
And from this, great things may happen!