Pipelines not always running on commit

Summary

Sometimes you could notice that some of your commits didn't trigger a pipeline build, even though it should be as per the bitbucket-pipelines.yml  configuration.

Diagnosis

Accessing the commits page of a given repo (e.g., https://bitbucket.org/<workspace-id>/<repo-slug>/commits/), you can see that some of your commits don't have a build associated with them.

Cause

The likely scenario is that multiple commits were made in a single push.

This is the expected behavior. Pipelines will only trigger a build in the last commit in a single push with multiple commits.

Solution

If you want to trigger a build to every commit, the solution is to push the commits individually.