In ODOO version 14, the option to reject a document by an approver is not a built-in feature. However, you can customize the system to add this feature by creating a new button or workflow that allows the approver to reject the document. This would likely involve creating a new state for the document, such as "Rejected," and modifying the existing workflow to include this new state and the corresponding transition from the "Approved" state. Additionally, you may need to update any forms or views associated with the document to include the option to reject.

Thank for  the explanation.

Generally any documents - subject accept or reject.

As no option in ODOO V14 - our consultants  completed the task by CUSTOM solution

Hi, currently I notice in Odoo 14 there isn't any option for not to sign. However, as long as any of the signee of the document failed to sign, or ignore the invitation email Request to sign, the document will be pending and not closed. 

In short, No action on the part of the signee is as good as displaying the intention of NOT TO SIGN. 

But, of course, one can always choose to customize the module to include the option of NOT TO SIGN and let user to have the option to click on it to show their intention.