Using three IFs vs using IF-ELIF-ELSE: former is faster

I wrote a code to find the ugly numbers. While trying to make it faster, I found that using 3 IFs instead of an IF-ELIF-ELSE made my code faster. I tried running the code for multiple iterations of n and found that this is true most of the time.

I feel that IF-ELIF-ELSE should be faster since if one of the conditions is met, it would not go into the others. But I am unable to find any logic in what actually happened.

Here is the code:

ugly = [0]*n
ugly[0] = 1
i2, i3, i5 = 0, 0, 0

count = 1

while count<n:
    n2 = ugly[i2]*2
    n3 = ugly[i3]*3
    n5 = ugly[i5]*5

    next = min(n2, n3, n5)

    if next==n2:
        i2 += 1
    elif next==n3:
        i3 += 1
    else:
        i5 += 1

    if next != ugly[count-1]:
        ugly[count] = next
        count += 1