Vue2 not change in Laravel 5.4

I´m trying to use Vue in Laravel. When I modify example.vue and add it in view, view no change. This is .vue example that Laravel has.

<template>
    <div class="container">
        <div class="row">
            <div class="col-md-8 col-md-offset-2">
                <div class="panel panel-default">
                    <div class="panel-heading"></div>
                        <div class="panel-body">            
                    </div>
                </div>
            </div>
        </div>
    </div>
</template>

<script>
    export default {
        mounted() {
            console.log('Component mounted.')
        }
    }
</script>

I tried to modify this file and run npm run dev, but view no change. ¿Any idea?

via El Hombre Sin Nombre