Every coin has two sides, though in-circuit test is a very powerful tool for testing PCBs, the in-circuit test also has some disadvantages which are listed as following.
1. As the fixtures are mechanical and require general and wiring assembly for each printed circuit board, they can be a costly item.
2. As the fixture is a fixed mechanical item, with the probes or "nails" mechanically fixed, any updates to the board changing the position of the contact points can be costly to change.
3. Electrolytic components can be tested for polarity only in specific configurations (e.g. if not parallel connected to power rails) or with a specific sensor
4. The quality of electrical contacts cannot be tested unless extra test points or a dedicated extra cable harness are provided.
5. It is only as good as the design of the PCB. If no test access has been provided by the PCB designer then some tests will not be possible.