How can I make Barrio SASS gulpfile coninue watching for changes

When running gulp. It runs and compiles SASS one time. How can I adjust the watch so that it continues watching for changes. Do I need to add usePolling: true or usegulp.series. I am following the directions exactly from the Bootstrap 4 SASS - Barrio Starter Kit

My setup: drupal core 9.1.10 bootstrap_barrio 8.x-4.33 bootstrap_sass 8.x-1.13 node v12.22.1 npm 6.14.12 gulp CLI version: 2.3.0 gulp Local version: 4.0.2 Vagrant on Windows using a Redhat 7 virtual machine

let gulp = require('gulp'),
      sass = require('gulp-sass'),
      sourcemaps = require('gulp-sourcemaps'),
      cleanCss = require('gulp-clean-css'),
      rename = require('gulp-rename'),
      postcss = require('gulp-postcss'),
      autoprefixer = require('autoprefixer'),
      browserSync = require('browser-sync').create()

    const paths = {
      scss: {
        src: './scss/style.scss',
        dest: './css',
        watch: './scss/**/*.scss',
        bootstrap: './node_modules/bootstrap/scss/bootstrap.scss'
      },
      js: {
        bootstrap: './node_modules/bootstrap/dist/js/bootstrap.min.js',
        jquery: './node_modules/jquery/dist/jquery.min.js',
        popper: 'node_modules/popper.js/dist/umd/popper.min.js',
        popper: 'node_modules/popper.js/dist/umd/popper.min.js.map',
        dest: './js'
      }
    }

    // Compile sass into CSS & auto-inject into browsers
    function styles () {
      return gulp.src([paths.scss.bootstrap, paths.scss.src])
        .pipe(sourcemaps.init())
        .pipe(sass().on('error', sass.logError))
        .pipe(postcss([autoprefixer({
          browsers: [
            'Chrome >= 35',
            'Firefox >= 38',
            'Edge >= 12',
            'Explorer >= 10',
            'iOS >= 8',
            'Safari >= 8',
            'Android 2.3',
            'Android >= 4',
            'Opera >= 12']
        })]))
        .pipe(sourcemaps.write())
        .pipe(gulp.dest(paths.scss.dest))
        .pipe(cleanCss())
        .pipe(rename({ suffix: '.min' }))
        .pipe(gulp.dest(paths.scss.dest))
        .pipe(browserSync.stream())
    }

    // Move the javascript files into our js folder
    function js () {
      return gulp.src([paths.js.bootstrap, paths.js.jquery, paths.js.popper])
        .pipe(gulp.dest(paths.js.dest))
        .pipe(browserSync.stream())
    }

    // Static Server + watching scss/html files
    function serve () {
      browserSync.init({
        proxy: 'http://orgex1',
        open: false,
      })

      gulp.watch([paths.scss.watch, paths.scss.bootstrap], styles).on('change', browserSync.reload)
    }

    const build = gulp.series(styles, gulp.parallel(js, serve))

    exports.styles = styles
    exports.js = js
    exports.serve = serve

    exports.default = build

Result when running gulp:

    [vagrant@vagrant6 presentation]$ gulp
    [15:47:33] Using gulpfile /var/www/html/orgex1/web/themes/custom/presentation/gulpfile.js
    [15:47:33] Starting 'default'...
    [15:47:33] Starting 'styles'...
    [15:47:37] Finished 'styles' after 3.62 s
    [15:47:37] Starting 'js'...
    [15:47:37] Starting 'serve'...
    [Browsersync] 3 files changed (bootstrap.min.js, jquery.min.js, popper.min.js.map)
    [15:47:37] Finished 'js' after 56 ms
    [Browsersync] Proxying: http://orgex1
    [Browsersync] Access URLs:
     ----------------------------------
           Local: http://localhost:3000
        External: http://10.0.2.15:3000
     ----------------------------------
              UI: http://localhost:3001
     UI External: http://localhost:3001
     ----------------------------------

I found my mistake. Since I am using Vagrant on Windows and a Centos7 VM box. When I run the gulp command on the box. My Windows host browser will not see the CSS changes. I had to install Nodejs on Windows, then run the gulp command in my theme folder inside Windows explorer. Then my Windows browser receives the Browsersync update and displays the CSS changes.