The reason I don't like this way is it can be harder to refactor. You don't want "return 1" happening if cond. For example, if you refactor to something like this:

    func hello() int {
       var result int
       if cond {
          result = 0
       }
       result = 1
       
       // New code with result

       return result
    }
      

Now, in this case, you don't want result to be 1 if cond, so you have to add the else condition. If you start with if-else, this is less likely to bit you in the future.

This particular bug just bit me in a bad way in production because I had what you have and and to make an quick production fix and did a refactor just like this and missed adding the else.