Custom object value sync between item and project when they are associated

Description - when custom object is created and it is shared between item and project, it doesn't updates/syncs in both places. 

Why is this feature important to you - it is a common field at item and project level so why update twice?

How would you like the feature to work - if updated at object type then it shd be updated across all common shared places 

Current Behaviour - it doesn't sync

For EG: I have a custom field "stage" at item and project level. i have checked box as i created this field. But when it is updated at project level, it doesn't show same value at item level and so user has to update twice.