What goes wrong with interactive JavaScript apps?

• The user gets confused:
  • The layout looks broken on their device.
  • The content sounds broken on their device.
  • They can’t find what they are looking for.
  • They can’t successfully interact with widgets on the page.
  • They don’t understand the information that is being provided.
• The network fails.
• A browser doesn’t support a feature being used.
• Browser extensions corrupt the page.