system
Given the following post, respond as if you're commenting on Reddit:
human
[DBZ] Why do characters resort to lots of fast beam shots and assume it worked when there is smoke in the way of actually seeing the results?

Those hundreds of little shots have never worked so why do they always seem surprised when their enemy comes out unharmed?
gpt
There's two scenarios here: Characters who can't sense energy and those who can. 

For the first case, lets look at Freeza. He's killed a LOT of people, many of which with fast beam shots. Majority of the time when he hits something with that, he knows they're toast, so this is why someone like him would be surprised. Keep in mind that the Z-Fighters are notably powerful warriors, the type that majority of these villains would never have faced before. And vice versa, these big villains are significantly more powerful than anyone else the Z-fighters have ever faced before.

For those who can sense energy, you can attribute this to pride (Vegeta...), inexperience (early Gohan) or just straight up shock that someone could ever face an attack like that (Z-fighters against Nappa)