For what reasons is it important to optimize compilers? Is there anything there a coder may find useful? When would it be inappropriate to utilize such a device?

Why is it that we are in such desperate need of effective compilers? If you were a programmer, what type of software would you develop for one of them if you were given the opportunity? Nothing even somewhat similar to this could ever be considered useless, right?

What are some of the numerous characteristics that a compiler needs have in order to create code that is both accurate and efficient? Explain?

The need to optimize compilers begs the question: why? What kind of code would you use to actualize a program? Do any situations arise in which using such a gadget would be counterproductive?