What are the disadvantages of a circular saw?

Cuts in one direction, not used for tight curves.

If material is not supported properly, blade can bind.

Probability of kickbacks when using dull blades, untrained personnel, knots or nails in cutting path, and blades binding.

Not for use in tight quarters.

Blades can snap and become projectiles if not cared for properly.

Creates high amounts of sawdust/debris, need to be used in a well ventilated area.

ANS 2 - All good points -but on the other hand, a good circular saw with a good blade, in the hands of a pro can be the most useful tool on a construction site or home workshop. A sensible worker will have a sabre saw for curves and a reciprocating saw for tight quarters or hard to get places.