You've been tasked with writing code to call the criticalOperation() method. The method returns a boolean value indicating the success of the operation. Your tech lead, who might have unconventional ideas, has instructed you to keep calling this method repeatedly until it returns true.

The challenge here is that we'll never be certain when the method will return true, but we hope that eventually it will. A success may occur during the first call, 3rd call, or 100th call. The loops we've looked at so far won't solve this problem because we don't have a list or indices to loop through. We need to perform a task repeatedly, but we don't know how many times to execute it in advance. This is where a while loop comes in.

A while loop executes a block of code repeatedly as long as a certain condition is true. The loop will continue to execute until the condition becomes false.

The general syntax of a while loop is:

while(someCondition == true){
     // some action that runs as long as the condition is true
}

// code below executes once someCondition is false

We can declare a boolean variable named isSuccessful to keep track of criticalOperation()'s result. As long as isSuccessful is false, criticalOperation() should be continuously called until it returns true.

Boolean isSuccessful = false; 

while(!isSuccessful){
     isSuccessful = criticalOperation(); 
}

This solution works but without a proper mechanism to ensure that the code stops running, we run the risk of encountering an infinite loop. This means that the criticalOperation() method could fail indefinitely, causing our code to execute indefinitely. Such a scenario will exceed Apex's runtime limits and halt our program.

Let's incorporate an upper limit of three on the number of retries. If the criticalOperation() method is unsuccessful after three attempts, we will exit the loop, ensuring that we do not encounter an infinite loop scenario.

Boolean isSuccessful = false; 
Integer retryCount = 0; 

while(!isSuccessful && retryCount < 3){
     isSuccessful = criticalOperation(); 
     retryCount++;
}

During each iteration of the loop, we will increment retryCount by 1. We will use this variable to determine whether another iteration of the loop is necessary by checking its value in the loop's condition. It's important to note that the conditions of the while loop can be as simple or complex as necessary to fit the requirements of the task at hand.