Can someone shed some light on what are specific differences between user tasks and user goals?
Personas focus on goals while market segment focuses on tasks.
I'm unclear on what exactly "tasks" means in this context.
User goal is a final state which user strives. To get the goal user should perform some tasks (user tasks).
How different it could be to satisfy user tasks vs user goals?
Offline: car rental company.
Online: coffee machine selling site.
task is to choose and buy coffee mashine easily.
Solution: machines comparison functionality, ordering by price functionality, easy payment procedure.
goal is to have a cup of coffee every morning.
Solution: in addition to buying task provide also set of recipes of making great coffee and coffee delivering service or so.
Also an example of tasks vs goals is in Norman's article.
So, goals is more high level comparing to tasks. And tasks are ways to reach the goal. More frequently we think in terms of tasks, that limits ourselfs or our users.
To switch from tasks to goals you can use very simple but extremely useful 5 whys technique.
In my opnion :
Task are more "incomplete" than goals.
Also, tasks are generally the nitty gritty "not fun" part.
Goals give you a sense of accomplishment are fun and are 'complete' in the sense that you wouldn't have to do more to feel satisfied.
Tasks can also give you a sense of satisfaction and can be fun but relative to completing a goal their level of return is less.
For example, running a marathon might be a goal while weekly training is a task.
The training itself would be satisfying but doing a marathon is even more satisfying than the training.
The other way I look at it is, goals are the things people imagine themselves completing and feeling good about. Tasks are the things that people didn't think of having to do to complete the goal.
Of course this is all subjective. Sometimes a task can be an intermediary goal. Like the marathon example, an intermediary goal/task would be to run a half marathon.
To achieve a goal you need to perform some tasks. E.g. your goal is to learn playing golf. So you need to perform tasks - buy golf clubs, study in golf school, work with trainer, practice, etc.
Goals are also in an upper-level than tasks. So, users can have some non-clear, unmeasurable objective as a goal (p.e.: "loose some weight before summer") which is not directly related to a certain amount of tasks.