To address the estimate point I must say that there’s nothing in scrum preventing you from trying things before giving an estimate. Having a task specifically

To address the estimate point I must say that there’s nothing in scrum preventing you from trying things before giving an estimate. Having a task specifically to do exploratory coding is, in fact, encouraged by extreme programming. Even after that if you find that you estimated completely wrong it’s no big deal. That’s what it is for. You need to find mistakes. I’m not saying this is the case but it seems that your particular implantation of scrum is very poorly done. Especially if your only resource is the scrum guide. The actual book written by Ken Schwaber mentions that you can add things to a sprint of work is completed before the end of the sprint. This is part of the process and just like in the previous case is also saying that your knowledge is lacking because you finished the work before you thought you would. Agile methods are tools to help improve the cadence and predictability of software delivery.