Way i see this there is no proper way to do and fully success Agile the way they document it. so every company make there own way to handle Agile. but to obtain a certificate for a company they document it like they do it like the document says. what i meant is this
You plan a sprint for 2 weeks and according to the agile that is what you need to deliver with in those 2 weeks. during this 2 weeks you will not change the Sprint items right? if you cannot do things they will be the first backlog items for next sprint. so if customers reporting a bug and guys find that to solve this you immediately need to change the design. and this will effect the current ongoing sprint items. so how you handle this? i guess there is no better answers to questions like this in agile methodology.
Valid point.
There is a proper way to adopt a fully successful agile framework and companies do it. To understand this you need to know the framework well and develop an agile mindset.
If you keep adding new features to the sprint backlog during the sprint then you lose the whole purpose of agile. i.e. incremental delivery/timeboxing
However, when you list the features in the SB you calculate the team velocity and most probably keep a buffer of 10%, this is mainly for bug fixes, not new features.
Also, tailoring happens, in scrum, there are mandatory components (Eg: you must conduct all the 5 scrum events) and the rest can be tailored as per your business need. However, adding features to an ongoing sprint violates the scrum methodology. You fall into a mini waterfall!
Hybrid is a solution for the issue you stated. Also scaled agile can be implemented based on the size of the operation.
Coming back to my question; I wanted to know which companies practice Agile as Agile, not hybrid, not predictive. Just pure Agile.