I'll be the first to admit I'm not very good at this game, and my inability to spot/airdodge/roll well holds me back. These boards have plenty of good folk, could someone go over the dodging mindset? I'm certain I'm not the only one who could use such a guide...
To kind of go off what the person above me said, it should be a mix-up. And to elaborate, most of the time dodging and rolling should not be used as your first defensive option. Shielding is first and foremost your best way at dealing with your opponents attacks. Get in the habit of of shielding frequently and moving around the stage by running (or walking is actually best most of the time) and shielding to deal with your opponents attacks.
The only time you want to dodge is if for some reason you can't block your opponents attacks. The most obvious case is the situation of grabs because they can't be blocked. Another less obvious situation is when your shield is weak and either won't successfully block the attack (getting shield poked) or even worse you risk your shield getting broken. Then a dodge is the better choice but comes at a cost. With a dodge you must be sure the exact time the attack will come and you have to execute. If the attack doesn't come the exact moment you thought then you will likely be hit (that is why shielding is better you don't have to know exactly what your opponent is doing, you just need to generally know). Another example of when a dodge is favorable if blocking the attack will prevent you from doing something you want (like punishing if hitting your shield pushes you too far back or puts you in too much shield stun).
Rolling is the worst of the 3 options, it is essentially a dodge that moves. So you can use it in most of the same situations as a dodge but are able to move somewhere else. This option also comes with a cost (even from dodging). This maneuver takes longer to perform, so if you guess the timing wrong (just like with dodging) you are likely to be hit, AND your opponent has even more time to hit you. The next cost is that rolls move a set distance, so you have no flexibility on where you will come out. Your opponent needs to be at exactly the right distance to get a punish off unlike dodge.
The most important cost, however is that rolls are vulnerable on cooldown (or ending, just like with dodges) but they are ALSO vulnerable on startup (or at the beginning) if you are blocking something, and decide to dodge you will not be hit until the end of your dodge. If you are blocking something and decide to roll you can be hit BEFORE and AFTER the invincibility on the roll (which is in the middle).
There are definitely situations where a well times dodge or roll can win you the game, but it needs to be a mixup or a read. 9 times out of 10 shielding is your best option (I didn't bother mentioning that simply avoiding the attack by simply moving out of range is actually better than shielding half the time).
