Remarketing attracts previous leads to your webinar, which helps prevents losing leads. It also increases the chances of conversions, because previous visitors provide a high potential of conversion.
Communicating with your old leads helps build your credibility and revive them as your new prospecting leads for your product or services.
It is really difficult to get an audience to be a part of your webinar. You always need to look for a topic from your niche that is trending to be able to capture the attention of a large audience. Do some research and look for customer problems. Be relevant and informative with your webinar topic to encourage more people to attend your webinar.