Level 1
Your work is not good enough. Experience is lacking perhaps. Effort is lacking maybe. The criticism is valid, worth noting and acting upon.
Level 2
There is a difference of opinion. Your output, your deliverable is a quality one but there is a difference of opinion. This might be something worth considering to add even more value to your output or it could be a bit of politics. The criticism is worth considering and exploring to decide whether your product does need to be improved or the relationship with an individual needs to be bettered.
Level 3
You've reminded someone what they might do if they got their own act together. What you have produced does not need to be changed in any way but the critic will attempt to lessen their own vulnerability by criticising your work. Avoid politicing and produce great work.
Level 4
The attack has changed from product to personal. You really are getting some people thinking. You really are doing some worthwhile things. Stay balanced, consider all points but don't go off path as you begin to discover your greatest works.
Level 5
The continued comments from all quarters will-as long as you stay balanced-produce friction which will help you produce your greatest works.
Level 6
Oh oh. You are 'it'. You are the new thing. They finally get it. But: your ego kicks in. There is no room for criticism. You refuse to listen. Your products wanes.
Level 7
With luck, you have learnt your lesson. Humility over ego. Listen over judge. Grow over stay-the-same. Criticism continues but it's just grit to wonderful output.