Why press "i" during mammoth boot up?

Why Oh Why?

redhat 9 system - swap partition on /dev/sda1 is commented out in /etc/fstab.

After major power fail, boot fails unless i is pressed for Interactive startup.

It hangs after enabling local filesystem quotas ...OK.
Which should have 'enabling swap space' as the next line showing on the console in a successful boot sequence.

So: is it related to having no swap partition/file?
Is it something else entirely?
sun cobalt lx50