Quotes from The Art of Software Development - James Shore

• It is difficult to imagine how software will work even before we begin using it. 
• It is harder to think of absolutely everything your software needs to do. (We cannot specify all the requirements upfront.). That is requirements are emergent. 
• Core concepts of Agile are:
• Rely on people: 
• Trust people
• Put decisions in their hands
• Base your work on healthy collaborative relationships
• Deliver Value frequently
• Experiment
• Seek feedback
• Use feedback to improve your product
• Eliminate waste:
• Work in small increments.
• Embrace possibility of failure
• Others are 
  • Problems due to wait time
  • Lack of knowledge
  • Time consuming daily stand ups
  • Lengthy planning and other meetings
  • Manual regression takes long time
• Seek technical excellence:
• Start simple, add complexity only in response to needs. 
• Create systems that are easy to evolve

The road to agile mastery - Shu Ha Ri

Sprint goal

Sprint goal ties up to the product goal which again aligns with the product goal all of which aligns with the Product Strategy. This goal aligns with the product vision. 

Sprint goal >> Product Goal >> Product Strategy >> Product Vision >> Company Vision

Image courtesy: Roman Pichler.

Sprint goal: is a brief explanation of what the team plans to achieve during the course of an Agile sprint. 

There HAS to be a single sprint goal towards which the team will focus all its energies and try to achieve by end of the iteration. However, as an antipattern it is seen teams have multiple sprint goals - as a summary of all the assorted pieces of work the team may be working on. 

Having a single goal

Having a single goal forces you to pull users stories that are aligned to the finely-grained product area. (Allen Holub). This also means you may be working on some lower-value stories just because they are aligned. That leaves lots of high-value work items in the backlog simply because they are unrelated to the Single Goal. 

Product goal: describes the future state of the product. It is a long-term objective towards with the scrum team work. 

Product goal is best used to describe a specific or a measurable benefit or outcome a product should create in the course of say next two to six months.

Example: acquire users, increase conversion rate, generate revenue, reduce technical debt, etc.