As a programmer, you will know how difficult it is to work on code done by someone else. Do not mess with code if you don’t know what you’re doing.
If you had been a programmer for more than two or three years, you have probably been significantly slowed down by someone else’s messy code. The slowdown can be considerable & you may find yourself moving at a snail’s pace. Each change you make to the code may break other parts of the code. Every addition or modification to the system needs to be understood so that more changes can be added. Over time the mess can build up big and deep that you cannot clean it up. There is no way at all.
As the mess builds, the productivity decreases almost reaching zero. As productivity decreases, more staff may be added to the project in hopes of increasing productivity. But being not versed in the design of the system even they too can’t do much to improve the system. Furthermore, they too under horrific pressure to increase productivity start making more and more messes which drive the productivity ever further toward zero.
It’s better to review the code before proceeding. At times it’s just not worth changing but, if it is small enough you can give a one-shot re-write it. But don’t change key or critical code that others rely on or use regularly without either approval or code review. Hence it’s always better to build code from scratch for better results.
