Inexplicable Subscript: Find That LBound(sourceData) = 1 And UBound(sourceData) = 11, As Expected

I have set up a worksheet to demonstrate how arrays work--and find that I need to learn more about the topic myself! The code below reads data from Column A into an array, sorts it, and then writes the sorted data to Column B. In the example I have created there are 11 data values in Column A. When I break at the indicated line of code, I find that LBound(sourceData) = 1 and UBound(sourceData) = 11, as expected. However, at the indicated line of of code, when i = 1, the reference to sourceData(i) results in a subscript error.

Public Sub AddSortedColumn()
Dim sourceData() As Variant
sourceData = Range("A1:A" & Range("A65536").End(xlUp).Row)
Dim swap As Boolean
Dim i As Integer
Dim save As Variant
swap = True
Do While swap
swap = False
For i = LBound(sourceData) To UBound(sourceData) - 1..................