The 'else' in my if/else statement never happens - can someone explain why? [duplicate]

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• Is `if (condition = value)` the correct syntax for comparison? 5 answers

Just doing the codecademy course, everything works when I run the code except for this if/else statement. When it gets to that, no matter what I input for the userAnswer prompt, I just get the 'if' output. Can someone explain why? Been reading this thing 100x and the answer isn't jumping out at me. Thanks a ton.

var userAnswer = prompt("Do you want to race Bieber on stage?");

if(userAnswer="yes") {

    console.log("You and Bieber start racing. It's neck and neck! You win by a shoelace!")

} else {

    console.log("Oh no! Bieber shakes his head and sings 'I set a pace, so I can race without pacing.'")

}