Loaded 0 entries from cache. (0 were stale)

[faganer]

"webpack": "^1.13.1",
"happypack": "^3.1.0",
"babel-loader": "^6.4.1",

rules:

rules: [{
  test: /\.js$/,
  use: ['happypack/loader?id=babel'],
  include: [
    path.resolve(jsDev, "src"),
    path.resolve(jsDev, "base"),
    path.resolve(jsDev, "module")
  ],
  exclude: path.resolve(__dirname, 'node_modules'),
}, ],

HappyPack:

new HappyPack({
  cache: true,
  verbose: true,
  verboseWhenProfiling: true,
  debug: true,
  threadPool: happThreadPool,
  cacheContext: {
    env: process.env.NODE_ENV
  },
  id: 'babel',
  loaders: ['babel-loader?cacheDirectory'],
}),

But build:

Happy[babel]: Version: 3.1.0. Using cache? Yes. Threads: 11 (shared pool)
Happy[babel]: Loaded 0 entries from cache. (0 were stale)

Why?