Why are Advanced Machining / Material Removal Processes Needed?

With the advent of new materials and the requirements of complex features on them, there was a necessity to develop new processes. Some of these features are:
1. Related to material properties:
 High hardness  High strength  High brittleness 2. Related to workpiece structure:
 Complex shapes  Typical thin and delicate geometries  Parts which are difficult in fixturing 3. Related to requirements in high surface finish and tight tolerances.
4. Related to controlling of temperature rise and residual stresses.