What is the theory behind the insect offspring being so aesthetically disgusting as compared to the offspring of other species?.

Animals don't have to follow our rules. They live their own lives.

What is your mental scenario?
I see two possible ways of considering your question:

1) Insect offsprings are that digusting things, I can not understand why insects have those weird youngs, somebody explain me.

The answer, as some others here have told you, is that you should consider insects with an insect eye. Insects in general, and there are...around...950,000 species of insects...are not meant to be cute to our human eyes.
Besides, many of them are not even meant to be in their mom eyes, because they don't recieve parental care once they are born.

In short, consider insects in the context of their own needs and adaptations for survival.

2) Some insect offspring seem to be deliberately disgusting, could this be an adaptation for something?, theories?.


Quite a few:
- For example many catterpillars advice that they can be urticant.

Very urticant, no need to test. I did once, and yes, they are. This is not my arm, by the way:

The truth is that is much more efficent -in terms of survival- to be easily recognized as urticant and hence possible agressors abstain to harm them, than being incredible dangerous but not advicing it, and wait until a agressor learns it.

In short, consider insects in the context of their own needs and adaptations for survival.