Zero endorsement blocks

Question

It has happened in the past that certain blocks get 0 endorsement. Like this one for instance

https://tzscan.io/103652?default=endorsement

What conditions lead to such 0 endorsement blocks ?

Answer 1

A baker must include endorsement operations when baking blocks. If the baker doesn't include any endorsements, than the result is a block with 0 endorsements.

The reasons a baker doesn't include any endorsements could be:

1. Most likely, the baker's node doesn't receive the endorsement operations, likely due to poor connection/not many connected peers
2. The baker purposefully excludes endorsements, although this is unlikely
3. There are no endorsements, potentially because another block was being endorsed due to a chain split, but the current block has then become the dominant chain.