What factors make it difficult for congress to pass laws ?

It takes many days and most bills get vetoed or die as most people would say because the  majority rule wins

i think it can have both positive and negative effects on businesses.

for example:

lets say you own a small business and taxes go up 4% that means it is going to cost your business more money to buy product to sell. but at the same time you make more money from the tax rise.

that is my theory.