For loop in simple R function is spitting out null vector

Question

I don't know why this is occurring, but I wrote a simple function and when I use a for loop within my function it keeps on spitting out a null vector.

power_vector_sample_size_sim = function(alpha){
  
  power_value_vector = vector(mode = "numeric")
  
    for(i in 1:10){  
    power_value_vector[i] = power_calc_simulation_by_samp(sample_size_1 = i, alpha_1 = alpha)
   } 
}

Here's the thing. The individual parts of the for loop work just fine and give me the desired result: a vector of length 10. That is if I just highlight the initialized variable and the for loop, the desired result comes about. But as soon as I try to wrap this up in a function then it goes null. I should add that above I have the argument alpha in the code, but when I was testing it I was using a numerical constant getting my desired results. I feel my scoping of the function is right, but something very small is stopping it from working. Thoughts?