Full overlay, partial overlay and seamless doors can all be constructed using different forms of pivot hinges. Because the hinge only rotates on a thin single point axis, it can be difficult to install them level. If either hinge is slightly askew, the operation of a door that have pivot hinges will function improperly and quickly break down the hinge itself. Pivot hinges are perfect for creating hidden-hinge designs but they tend to be significantly more fragile than other more advanced hidden hinges such as cup hinges. Since they are of simple design, pivot hinges tend to be very inexpensive.