Desacordation with the final of Slam Dunk

Slam Dunk is a manga the plot is, basically, the life of a student that is plying basketball and how he and friends win basketball games.

There has been an unfinished version of the manga into anime. I hoped for an end, but they did not want to continue the anime. Then, as I really wanted to know the end, I saw Slam Dunk in manga. But I didn't like this end. How could the main character finish he is invalid? I do not understand for what they did a final as like this. They could do another final, for example, the mai character and his team won the nacionals and they continue play basketball other year. I'm very angry with this final. I would have been preferred do not know the final.