Of course I can, and this has been explained MULTIPLE times. Miners want to maximize their revenue. Users want to minimize their fees. If miners always include every transaction regardless of fees, there's no incentive for users to pay fees. The only way for a market for fees to emerge is if there is competition for transactions in a block. That means that miners have to leave some transactions out. But which transactions should they drop? Obviously...the ones with the lowest fees per kilobyte. Or to put in other terms, a market for fees can only emerge when block size is limited.

I think that when people come on here and post claims that there should be no limit on block size that means either they did not bother to get acquainted on the subject by reading the exist posts, or they simply do not have the capacity to understand regardless of the amount of explanation provided.