Without a quorum, a meeting can talk but can't act: votes taken without one may be invalid. The quorum for owner meetings is set by the association's bylaws and state law, often as a percentage of the total voting interests. Board meetings have their own, separate quorum.
Many associations struggle to reach quorum at annual meetings. Collecting proxies before the meeting is the most common fix. Some bylaws or state laws also allow a meeting that fails to reach quorum to be adjourned and reconvened with a lower requirement.
Record in the minutes how quorum was established (how many owners attended and how many proxies were counted) before any vote is taken.
Free resource: HOA annual meeting checklist.