Why I need MW20?

I usually see people selling leech using Smegas and they like to say they have MW20, can someone tell me what's the difference?
First I tought it helps the others to get more mana when they level up, once MW20 would give +10% of your INT. But now I realized MW20 only applies at your BASE INT, not your TOTAL INT, so this dont make any difference for people who has 4 int.
Hope you guys understand what I said, I'm brazilian and can't speak english very well, sorry for that (anyway, the first line of this topic is what matter).
Thanks.

 

Some people put Base INT on their characters for big washing gainzzzz

 

A lot of people who leech add points to int, so for them mw20 does matter.

 

There are people who apply their AP to Base INT so that they can get an overall better INT if they don't have a lot of INT gear. There are also those who MP Wash and have high Base INT.

 

Thanks everybody! I got it xD

 

I've a NL myself, and my base INT was 380. MW20 gives me an additional 38 more INT; which equivalents to a marginal gain of 3 - 4MP per level.