Why I can complete the task without completing sub-tasks?

[Lukasz]

Why I can complete the task without completing sub-tasks?

How can I change it so:

Epic can be completed, when task is completed, task can be completed when sub-task is complete?

[Juan Carlos Vera]

In Jira, it is possible to complete a task without completing all of its sub-tasks because sub-tasks are considered to be independent and optional components of a task.

If you want Control these options... you can do it in the Automation Rules or doing validations in WF before Close a tassk or Epic

[Lukasz]

What is the point of blocking the task then? Shouldn't a task block completion of my Epic? Please see screenshot, ou have task which blocks epic, but epic can be completed anyway.

What's he point of linking them?

[Nic Brough -Adaptavist-]

Epics are different, they have two status.

As issues, they have their own workflow, the same as any other issue type.

But they also have an Epic Status, which is to-do, in-progress, done.  This has nothing to do with the issue workflow, it's derived:

• if there are no stories for the Epic, or none of the stories have moved out of a to-do category status, then the Epic status is to-do
• if any stories are in an in-progress status, the Epic status is in-progress
• if ALL the stories are in a done status, then the Epic is done

You can progress the Epic through its workflow if you want to, even completing it when it has open stories, so it has a done status.  But the Epic-status is defined by the state o the stories

[Lukasz]

Cranky, this seems so complicated 

[Nic Brough -Adaptavist-]

It is a little complex, but so is what people are trying to do here with Epics (and there's a long history of how they've been implemented in Jira, and ended up in what I can best describe as a "clunky" state)