Velocity in hours

Can you explain in details why it is wrong to calculate Velocity in hours?

@Anahit Marutyan, In my opinion, there is nothing wrong with calculating velocity in hours, infact some people use ideal days, BUT, the main reason it is advocated against is because there might be some disadvantages like:

• Estimations may happen linearly i.e. 1,2,3,4,5,6.... etc (how can you accurately determine the exact time?)
• It may lead to a sense of a committed value i.e. it could be questioned why something went over a specific time 

Estimates should be estimates and that is why the Fibonacci sequence is often recommended to keep the estimates less linear and predictable. The farther you estimate on the Fibonacci scale the more there is uncertainity and perhaps complexity.

These are just my thoughts, I'd love to see others add on or correct me if I am wrong.

I suppose you could do that but changing the name from velocity to 'hours worked' might be more appropriate. Using hours takes away from some of the benefits to relative estimation that story points can provide over time. 

If you're familiar with the company weight watchers they've become very successful by putting specific foods into a 'point' system. Depending on your goals you can eat a certain amount of points per day (your daily velocity). They may make something like a slice of pepperoni pizza into 5 points instead of calculating the calories of the cheese, crust, sauce, and pepperoni which allows people to easily compare the food to other foods and understand what how much they can eat in a day to hit their goals.

When making tracking calories fast, simple, comparable, and easily trackable people seem to have greater success since it requires much less effort to stay disciplined. I believe Story points have gained a lot of traction for similar reasons. 

I don't think using hours is wrong persay, however, if the team is using hours it may require more time and discipline to do it well. Hours are very granular and open themselves up to a greater degree of inaccuracy when it comes to complex problems. Having a process to deal with unknowns instead of just throwing out a giant hourly estimate that could be held against the team later may be advisable as well.