so i was at jellies grinding for loots , i use cry bow , karils , and other ranging equipment. while im grinding there , my equipment gets degraded as it should be. But , i notice that when my equipment gets more degraded , the loot somehow get lousier . And i have tried experimenting a bit (observing loots when armor at certain condition) . and it is true, lousy armor give lousy loot .

so here is my question , is it happen only to me or anyone else to ?

That must be coincidence

Since armours have nothing to do with drops you receive.

That must be coincidence

Since armours have nothing to do with drops you receive.

^^
It is only conicidence.

That isn't possible, that's not how barrows armor works.  It's just based on luck.

There is no relation, I assure you. The only aspect armors grant is stats.

Don't blame on armor lol blame on your luck.
I went to spectral for about 2 hours (around 20 - 30 trips back and from; banking), and I never get any armor/weapon from them 2 days ago. Yes I complain because there was an update on every monster's drop log and they made more items drop by them. So I thought that maybe because of that it was harder to obtain another piece of armor/weapon. Then 10 minutes later I got a corrupt whatever it is I forgot.
Anyway, what I'm saying here is you're just not lucky like me there. I didn't blame it on the armor nor how fast I can kill it. Sometimes I got something good within my first kill like I got my Zuriel Staff from them when I just came back from banking.

This is purely down to luck, as everyone has already said.

If you're ever unsure on what specific armours do, there is always our Wiki page.