Tiny cracks that occur on the ends of your teak furniture (in fact all outdoor furniture made from wood), such as the tops of legs or front of arms, are known as “end check.” Checking is caused by shrinkage differences between the surface and the interior of drying lumber. Since the ends dry first, they tend to shrink first but are restrained by the swollen interior. This differential results in stresses building up near the surface, which causes the teak to check. End checking is completely normal for teak furniture (again for all wood furniture used outdoors) and does not affect the structural integrity of the furniture.