No translated doc pages whould default to english instead of failing.

See  CS1157482 for more details.

This link works https://cloud.ibm.com/docs/cloud-foundry?topic=cloud-foundry-what-s-new-in-ibm-cloud-foundry-enterprise-environment&locale=en

But this one does says that the page does not exist: https://cloud.ibm.com/docs/cloud-foundry?topic=cloud-foundry-what-s-new-in-ibm-cloud-foundry-enterprise-environment

The reason is that the page is not yet translated to spanish.

I would suggest that if a doc page does not exist in a local language it should default to english or offer more chances instead of displaying that the "page does not exist".