Even teak furniture will rot given the right/wrong conditions. Due to injury I was unable to look after the garden properly for 2 or 3 years and a good quality teak bench was left under an overgrown pergola all that time. When finally retrieved, a section of the back had completely rotted away.
The conditions would have been exceptional, i.e. wet, humid and dark with little sun or air movement. Just don't think that you can automatically assume that teak will simply last a lifetime.