How does everyone build an EDH deck, in general? Do you:
1. Select a theme, such as artifacts or goblins, and build a deck around that theme, with the general being a lord that helps that theme, but isn’t necessary to win,
2. Select a general, and build a deck around maximizing the general’s abilities, usually winning with the general,
3. Build a deck without any purpose, and use something like Phage the Untouchable as your general (if you haven’t already noticed, you lose when you move her to the field),
4. Something else?

All of the above?

Some of my decks are general driven (Thada Adel, Azusa) some are good stuff (Rafiq, my upcoming Sapling repeat, Kazuul) and some are theme driven (Group Hug, Allies)

There's no hard or fast rule, you get an idea, it can be a theme and/or a general or a colour selection and you go from there.

Why?

Same with me.

Most of the time, I try to pick a color combination I haven't used yet, then find an interesting and seldom-used General and build around him/her/it in some way. That's how my Ertai, the Corrupted deck came to be. Other times, a newly printed General is so exciting to me that I dismantle an existing deck to build the new one. That's how Azami became Thada Adel, Acquisitor.

By the way, ibstudent220, this kind of thread is usually put in the "Strategy" subforum, not the "Decklists" subforum. Welcome to the forums.