Difference between gerunds and nouns ending in -tion

Question

As we know, gerunds have the same function as nouns and can be substitute in noun phrases. Additionally as far as I know, meaning of them would be the act of doing that verb. (I don't know whether this is correct or not, this is my intuition though.)

• Creating : An activity in which we are creating something.
• Cleaning : An activity in which we are cleaning something.

In the other side, we have noun "Creation" with meaning:

the act of creating something, or the thing that is created:

_{Source: Cambridge Advanced Learner's Dictionary 4th edition}

However, we don't have noun "clean + tion = cleanation". My questions:

• Why don't some verbs have "-tion" nouns?

• What is difference of meaning between gerund and "-tion" nouns? (for example: transformation and transforming)

Answer 1

The gerund refers to the act or process of doing something - the activity itself and nothing further.

The -ion form of a root can mean the act of doing something, but usually leans toward meaning its result, effect, or manifestation - something that persists or evidences after the activity.

Why don't some verbs have "-tion" nouns?

This may be a better question for https://english.stackexchange.com, but briefly looking into it, -ion comes from Latin and is generally used with words of Latin origin. Non-Latin words - such as those that are part of the Germanic "core" of English (e.g. all the irregular verbs) won't work with -ion.