These are some rules that will help you stay productive.
Ideally, you should point out any problems with a work item when you are first assigned it in Sprint Planning. However, sometimes you think a PBI will be fine, but then you run into blocking issues during the Sprint. In that case, you shouldn't wait until the next Sprint Planning because that is burnt time being blocked. So, you are forced to do some googling, and investigation on how to move forward. These moments can be stressful, especially for junior developers and the question arises... "When should I ask for help?"
Asking for help should follow 4 phases:
- Determine if it's time to ask
- Do your due diligence
- Figure out who to ask
- Prepare to talk to a senior
Sometimes you can set a task or be given work that ends up taking much longer than expected. Timeboxing sets a time limit to a task, after which you must stop and move on.