bonjour beat me to it, mostly. Lemme manke an analogy;
You can buy a a bread mix kit from the market and it will usually make a very tasty bread OR you can gather up all the ingredients mix the dough accordingly, let your yeast do its work to lighten up the dough, bake it.
Both make for very good bread but, there is just something to Homemade bread that just cant be beat, even from a bakery.
A lot of it may just be some connection that is made to the raw ingredients.
IMO, extract kits were a great starting point to get familiar with a large portion of the process and when short on time, I will brew more extract kits. But for the time being I have become bored with following the instructions and having simply a beer made to a style. All-Grain allows you to design your beer, your way.
PrOst!