“Welcome to our community; please make a massive commitment of time and energy!” isn't a very logical way to motivate people to do something, but that's exactly how a lot of communities and community products are designed. We, as the organizers, know what we want our members to do, but we're impatient and want them to jump right to the high-commitment contributions. For the majority of our members, it will take time for them to get to the point where they're committed enough to participate at that level. You need to make smaller asks first.
