Attrs behaves weird for each version of odoo

Question

I have seen weird behaviour of attrs in odoo for all versions (v8, v9,v10).

I want to know the reason why odoo frameworks behaves like that.

I have listed domains for m2m fields / o2m fields which I have tested for all versions, why it's version specific ?

I have written Yes if the domain is working for that version otherwise written No.