Progress and feedback:
The effects of providing progress feedback to users is well documented and proven to increase task completion rates and overall satisfaction. The rationale hinges on the idea that users who perceive that they are making progress are more likely to complete the task. Consider the following metaphor:
A friend tries to encourage you by observing “There's light at the end
of the tunnel.” The comment may help you persevere because, with the
end in sight, the remainder of the task becomes more pleasant or the
prospect of abandoning it more unpleasant. In either case, your friend
is trying to influence how you perceive the task to help you complete
source: The impact of progress indicators on task completion
Another useful analogy not directly associated with the web but based on the same principal is inflight entertainment systems that show flight path and other flight details.This feature is mainly available on long-haul flights help convey progress and shorten the journey!
Users seek completeness:
Progress bars drive users to fulfill tasks by clearly stating the goal and charting a path for the user to follow which in turn encourages the user to seek closure or completeness.
Closure (Reification) is one of the Gestalt Principles, which suggests that people perceive and look for completeness even if it is not entirely there as in the example below:
Although the panda above is not complete, enough is present for the
eye to complete the shape. When the viewer's perception completes a
shape, closure occurs.
source: The Gestalt Principles
The same is achieved using progress bars and visual clues that indicate progress and signal completeness.
How many steps needed for onboarding:
This really depends on:
- How optimised your onboarding process is.
- What users expect to achieve using your site.
- The structure of the tasks your are requiring users to go through.
Overall, if the process is long or complicated then try to be as transparent as possible which in principal could buy you some time and patience from your users.
Might be helpful:
Are form progress bars when each section has multiple subsections a