Question about removing "concatScripts" from the build task

'use strict';

var gulp = require('gulp');
var concat = require('gulp-concat');
var uglify = require('gulp-uglify');
var rename = require('gulp-rename');
var sass = require('gulp-sass');
var maps = require('gulp-sourcemaps');

gulp.task('concatScripts', function(){
    return gulp.src([
        'js/jquery', 
        'js/sticky/jquery.sticky.js', 
        'js/main.js'])
    .pipe(maps.init())
    .pipe(concat('app.js'))
    .pipe(maps.write('./'))
    .pipe(gulp.dest('js'));
});

gulp.task('minifyScripts', ['concatScripts'] function(){ 
    return gulp.src('js/app.js')
    .pipe(uglify())
    .pipe(rename('app.min.js'))
    .pipe(gulp.dest('js'));
});

gulp.task('compileSass', function(){
    return gulp.src("scss/application.scss")
    .pipe(maps.init())
    .pipe(sass())   
    .pipe(maps.write('./'))
    .pipe(gulp.dest('css'));
});

gulp.task('build',['minifyScripts', 'compileSass']);  //concatScripts removed because it is a dependency of minifyScript but does it have to be?
gulp.task('default', ['build'] );