Why should test points be added to pcb design?

Why should test points be added to circuit board design?
Circuit board design plus test points are not needed in PCB production, but ICT test after PCBA is completed, which is to test whether there is any problem in circuit board welding and whether the performance meets the requirements.
In the production of PCB, the circuit board also needs to be tested to see if the circuit is open or short-circuited. This one uses a needle bed to test against each network point.
The light PCB is fine, but the PCBA is fine, which is different. The components are all soldered. Especially for SMT components, if you use a needle bed, it is easy to damage the SMT components when the needle pokes them. What should you do? It is necessary to add additional test points on each line network for the needle bed to be connected. In this way, the needle bed will not hurt SMT components, and the needle bed will press to a flat test point. The test will be more accurate. In the early years, it was stipulated that 90% of the network should be equipped with test points.
There are some unavoidable disadvantages in testing with needle bed. There is a limit to the size of needles and the minimum distance between needles. It may be difficult for high-density circuit boards.
There are so many test points, which is really stretched for high-density PCB space, and it is certainly unrealistic. Now there are many untested points, and there are other testing methods. Such as JTAG test, X-REY test and AOI test. However, these tests can’t completely replace ICT tests in some places.
The above is the introduction of why test points should be added in circuit board design. I hope it can help everyone. Contact customer service and consult pcb design scheme.