Unexpected result when looping through mutable object such as lists?

#######      Unexpected results when looping through mutable list

nums = [1, 2, 3, 4, 5, 6]
nums2 = nums.copy()

# Unexpected result when looping through list and removing items

print("\nUnexpected looping results on mutable object\n")
for item in nums:
    print(f"Item to be Removed: {item}")
    print(f"List Before Remove: {nums}")
    nums.remove(item)
    print(f"List After Remove: {nums}")

# Using copy to remove unexpected results as each time through the list it is making a new copy of list
print(f"\n\nUsing copy to mitigate unexpected results while looping through mutable object\n")
for item in nums2.copy():
    print(f"Item to be Removed: {item}")
    print(f"List Before Remove: {nums2}")
    nums2.remove(item)
    print(f"List After Remove: {nums2}")