Short forms are good! When someone comes back to a form, you can present new fields and progressively fill out the profile of the visitor. Here's how.
For this feature to work properly, make sure Form Pre-Fill is enabled for visible fields, and disabled for hidden fields.
Go to Marketing Activities.
Select your form and click Edit Form.
Under Form Settings, click Settings.
Set Progressive Profiling to Enabled.
Okay, now let's configure it. Go to Field Details.
Drag and drop all fields that are part of the progressive profile set.
When done moving all fields, it should look something like this:
Select the Progressive Profiling box.
Now choose how many blank fields you want people to see from the Progressive Profiling box at any given time.
Click Approve and Close.
Nice job! The work you just did will pay off.
Experiment with this feature and be sure to test. It's advanced, but you can make your forms very dynamic this way.