For working on small tubes that must be cut to high dimensional accuracy, laser cutting is a good choice because the laser light used does not have any physical presence and makes no contact with the material. It does not push, drag, or impart force that might bend a part or cause flex that would have a negative impact on process control.
It also offers minimal thermal input, with fine control over work area temperature. This is important since small parts heat up quickly and might otherwise overheat or deform.
Laser cutting is highly focusable to about 25 microns, which is about ¼ of the width of a strand of human hair. This makes it feasible to remove the minimum amount of material to make the cut, resulting in extremely high precision and high accuracy.
Laser cutting technology has an extremely fine control of pulse width, power, and focus spot size. Because the laser cutting tool does not rely on touching the part, it can be oriented to make any shape or form. Not limited by physical cutting geometry, laser cutting can be used to make unique shapes.