Design a web-based offer claim form for clients and come up with two main directions for design.
In one, the user progresses from left to right with the summary / progress bar of the form displayed at the top.
In the other version, the user goes from top to bottom, the questions acting both as indicators of synthesis and progress.
What do you think is the clearest navigation model?
Jackob's law suggests that the more traditional layout is easier. But the feedback from stakeholders and users was strongly in favor of the vertical layout.
In your opinion, what could be the disadvantages of the vertical layout?