Development of the high quality software…
Development the high quality software…
Neither is correct, sorry. There are several issues:
- "of" is required – I'll explain why below
- "software" is a mass noun, not a countable noun, so "the" (or "a") is incorrect
- "critical" is not a noun, so "a critical" is incorrect
To understand why "of" is needed, let's look at a slightly different version of the sentence:
Developing high quality software is critical for the company.
In this version, "of" is not needed. "Developing" is the verb, and "software" is the object. So far so good.
What happens when we change "developing" to "development"? Well, "-ment" is a suffix that turns a verb into a noun. When you add "-ment" to a verb, the resulting noun can have a couple of different meanings:
- The condition brought on by the verb – enjoyment
- The result of the verb – accomplishment
- The process or action of the verb – management
"Development" uses meaning #3 – "development" is "the process of developing".
But because "development" is now a noun, we need "of" to indicate what is being developed – because a noun doesn't take an object in the way that a verb can.
Is there any difference between the rules when we're talking about the complete sentence or just short statement?
No, there's no difference. Although the "short statement" is probably not grammatical on its own; those are called "sentence fragments" and they are a grammatical error (and a larger topic).