Why fibre channel is better for DDT (direct data transfers) ELI5-Style.
Let's say that you need to send a package to Joe across town. You don't know how to get to Joe's house, but you know that he lives on 123 Mersenne St. You put the package in the mailbox (it's a really big mailbox). You know that the mailman knows how to get to Joe's house so you trust him to get the package there. Now here's the catch, you know the mailman knows how to get to Joe's house, but you're not sure if he's going to lose your package halfway there, so in the box you ask Joe to send you a letter back, just to say he got it. You don't want to send another package to Joe unless you're sure he got the first one (just in case the mailman has slippery fingers).
This is how Ethernet works. You can see how sending a lot of data will take a long time.
Let's say, however that Joe lives just down the street and not across town. Since you can now see the mailman take your box while standing at the mailbox, you can line up as many boxes as the mailman can carry and be sure that they are going to get there (because you can watch him take them there). Additionally, because Joe's just down the street you can use less packing material and a smaller address label on the package itself (thus increasing the number of packages Mr. Mailman can take to Joe's house per-trip).