Final answer:
The most common mistake when implementing while loops is forgetting to update the loop condition. Without updating the loop condition, the loop can become infinite and result in the program running indefinitely.
Step-by-step explanation:
One of the most common mistakes when implementing while loops is forgetting to update the loop condition. A while loop continues to execute as long as its condition is true. If the condition is never updated within the loop, it can result in an infinite loop, causing the program to run indefinitely.
For example, let's say we want to print numbers from 1 to 10 using a while loop:
If we forget to update num inside the loop, the condition will always evaluate to true (1 <= 10), resulting in an infinite loop.