Shiva, Hanuman, Ganesha and Gayati deities are shown with 5 heads in idols but not Vishnu or Durga? Whats the reason?

[![enter image description here][1]][1]

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  [1]: https://i.sstatic.net/0Ooar.jpg
  [2]: https://i.sstatic.net/2I6RM.png
  [3]: https://i.sstatic.net/mXaH1.jpg
  [4]: https://i.sstatic.net/mSCl8.png