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Why does adding another condition in my while loop force the turtle to win? (Multithreading)

Why does adding another condition in my while loop force the turtle to win? (Multithreading)

i'm currently learning about multithreading for my java class and part of the assignment requires me to race two threads (turtle and a hare) together and force one of them to win using the wait() and notify() methods (in this case the turtle thread).

public class Race {

    private Integer numberOfLaps;
    private Integer lapToStart = 2;
    private boolean isWinning = true;

    public synchronized void winner(Integer numberOfLaps) {
        while (!isWinning) {
            try {
                wait();
            }
            catch (InterruptedException e){}
        }

        this.numberOfLaps = numberOfLaps;
        System.
out
.println("Tortoise is on lap: " + numberOfLaps);

        isWinning = false;
        notify();
    }

    public synchronized void loser() {
        while (isWinning && numberOfLaps < lapToStart) {
            try {
                wait();
            }
            catch (InterruptedException e){}
        }

        System.
out
.println("Hare is on lap: " + numberOfLaps);
        isWinning = true;
        notify();

    }
} public class Race {

    private Integer numberOfLaps;
    private Integer lapToStart = 2;
    private boolean isWinning = true;

    public synchronized void winner(Integer numberOfLaps) {
        while (!isWinning) {
            try {
                wait();
            }
            catch (InterruptedException e){}
        }

        this.numberOfLaps = numberOfLaps;
        System.out.println("Tortoise is on lap: " + numberOfLaps);

        isWinning = false;
        notify();
    }

    public synchronized void loser() {
        while (isWinning) {
            try {
                wait();
            }
            catch (InterruptedException e){}
        }

        System.out.println("Hare is on lap: " + numberOfLaps);
        isWinning = true;
        notify();

    }
}

Output:

Tortoise is on lap: 1

Hare is on lap: 1

Tortoise is on lap: 2

Hare is on lap: 2

Tortoise is on lap: 3

Hare is on lap: 3

Tortoise is on lap: 4

Hare is on lap: 4

Tortoise is on lap: 5

Hare is on lap: 5

Tortoise is on lap: 6

Hare is on lap: 6

Tortoise is on lap: 7

Hare is on lap: 7

Tortoise is on lap: 8

Hare is on lap: 8

Tortoise is on lap: 9

Hare is on lap: 9

Tortoise is on lap: 10

Hare is on lap: 10

If this prints out first before the hare finishes, the turtle has won! Congrats

If in the while loop for the loser method is only the volatile boolean, both the turtle and the hare finish at the exact same time. however, if i add another condition to it

public synchronized void loser() {
    while (isWinning && numberOfLaps < lapToStart) {
        try {
            wait();
        }
        catch (InterruptedException e){}
    }public synchronized void loser() {
    while (isWinning && numberOfLaps < lapToStart) {
        try {
            wait();
        }
        catch (InterruptedException e){}
    }

the output becomes: