If statement issue (Javascript)

I'm trying to make a Catchphrase style game where the user gradually clicks squares covering a picture until they can guess the person in the picture. The relevant code and comments are below:

// One of three random images to be displayed when page refreshes.

        var randomImage = new Array();
        randomImage[0] = "/IMAGES/0.jpg"
        randomImage[1] = "/IMAGES/1.jpg"
        randomImage[2] = "/IMAGES/2.jpg"

        var randomNumber = Math.random();

        randomNumber = randomNumber * randomImage.length;

        randomNumber = Math.round(randomNumber);

        if (randomNumber == 0) {

            document.getElementById("backPic").src="../IMAGES/0.jpg";

        }

        else if (randomNumber == 1)  {

            document.getElementById("backPic").src="../IMAGES/1.jpg";

        }

        else {

            document.getElementById("backPic").src="../IMAGES/2.jpg";

        }

// When user submits their answer, if they are correct, they are alerted 'Well done!'

        document.getElementById("submitGuess").onclick = function() {

            var correctAnswer0 = "Terry";

            var correctAnswer1 = "Drogba";

            var correctAnswer2 = "Lampard";

            if (document.getElementById("userGuess").value == correctAnswer1 && randomNumber == 1){


                    alert("Well done!");


            }

        }

In the if statement above, I expect that only when submit is clicked, and userGuess is correct and randomNumber is equal to 1, that the user is alerted 'Well done'. However when the submit button is clicked when a different picture is displayed (i.e. randomImage[2]), it instead changes the picture to randomImage[1].

Can anyone help me and tell me why this isn't working?

Thank you!