Почему gulp не создает dist?

let project_folder = "dist";
let source_folder = "#src";

let path = {
    build: {
        html: project_folder + "/",
        css: project_folder + "/css/",
        js: project_folder + "/js/",
        img: project_folder + "/img/",
        fonts: project_folder + "/fonts/"
    },
    src: {
        html: "./" + source_folder + "/*.html",
        css: source_folder + "/scss/style.scss",
        js: source_folder + "/js/script.js",
        img: source_folder + "/img/**/*.{jpg,png,svg,gif,ico,webp}",
        fonts: source_folder + "/fonts/*.ttf"
    },
    watch: {
        html: "./" + source_folder + "/**/*.html",
        css: source_folder + "/scss/**/*.scss",
        js: source_folder + "/js/**/*.js",
        img: source_folder + "/img/**/*.{jpg,png,svg,gif,ico,webp}"
    },
    clean: "./" + project_folder + "/"
}

let { src, dest } = require('gulp'),
    gulp = require('gulp'),
    browsersync = require("browser-sync").create();

    function browserSync(params) {
        browsersync.init({
            server: {
                baseDir: "./" + project_folder + "/"
            },
            port: 3000,
            notify: false
        })
    }

    function html() {
        return gulp.src(path.src.html)            
            .pipe(dest(path.build.html))
            .pipe(browsersync.stream())
    }

    let build = gulp.series(html);
    let watch = gulp.parallel(build, browserSync);

    exports.html = html;
    exports.build = build;
    exports.watch = watch;
    exports.default = watch;