During the fight against Raditz, Goku actually manages to grab Raditz's tail and tells Piccolo to fire the Makankosappo. He eventually lets go of the tail when Raditz pleads for forgiveness, which leads Goku back on the ground, this time with broken ribs. Later on Goku somehow finds the strenght to sneak behind Raditz and lock him in a full nelson, telling Piccolo, once again, to fire the Makankosappo. When Piccolo asks Goku why he didnt grab his tail this time, Goku replies something in the sense of ''He can cut off his tail at will'' and we hear Raditz respond on this with ''(so) You knew that''........
This whole situation with the tail seems a lot more complicated than it would seem (or rather, I would like it to be more complicated than it seems
#1. Goku didn't intended to kill Raditz when it wasn't necessary once he had his tail, hoping that Raditz would be sorry and just leave, baring in mind that even if Raditz cut off his own tail he wouldn't be stable enough to fight, giving Goku and Piccolo the time to take him down anyway. This however wouldn't explain why he didn't grab Raditz's tail the second time.
#2. Situation #1 would be explainable if Goku would consider the possiblity that Raditz's stability wouldn't be affected by his tail being cut off, making Goku's action nothing more than a bluff. This is supported by Raditz's phrase ''You knew that'', implying that Raditz himself knew that he could cut off his own tail without being affected so much to incur serious danger. This however is not supported by the fact that Raditz, a proud fighter that he is, would consider begging for his life. But there is a possibility that Raditz desperately needed his tail with the full moon to conquer Earth as fast a possible and therefore cutting his own tail would be a final resort. Or that apart from being a proud fighter, he is also a dirty/cunning fighter that wouldn't mind using this sort of antics on the battlefield.
#3. Goku simply forgot that Raditz was able to cut off his own tail and was fooled by him but remembered it while his ribs were being wrecked. This situation would suggest that Goku did figure out that Raditz wouldn't be affected by his tail being cut off. But then again, why would Raditz beg for mercy? Because of the reasons mentioned in situation #2? Also, if adult Saiya-jins are not affected by their tails being cut off, why would Piccolo try to grab Nappa's tail after he learns from Goku that it's no use? Did he simply forget it by then too?
So aside from the question as to why Goku grabbed the tail, we can also ask the question whether a common adult Saiya-jin, such as Raditz, is affected in his stability after his tail is cut off.
And I do have one more possibility..
#4. Mr. Toriyama was picking his nose when he was creating this scene and I am reading way too much into things.








