Growth is an essential part of a community's evolution. Growth brings new members, new ideas, and new energy. It prevents stagnation. And of course, more members means more impact that the community has, and the more ambitiously it can pursue its mission.
Growth can also threaten a community. Growth can come from the wrong source or at the wrong time. A community needs to be ready to grow, with a plan in place for how to onboard and integrate reasonably-sized cohorts of new members. Premature growth can lead to frustration, chaos, a dilution of values, and even the departure of long-term, highly trusted members.
The Orbit Model and the concept of gravity can help you understand if it's the right time to grow, or if it's the right time to wait and focus on gravity instead. The determination is based on how well growth has been absorbed historically and the trajectories that recently added members have been taking.
Is gravity increasing as new members become more committed and present? Great! You should have no problem adding new members to the community.
On the other hand, are most new members stalling in outer orbits with little to non progression? You might be better served increasing gravity before driving more growth.
Historical baselines for common growth-related metrics will help us understand what's been happening to date and help us spot deviations in the future.
Start with establishing a baseline for your the size of your community based on monthly active community members.
Of course, "active community member" can mean different things to different communities, so we suggest using orbit levels to define the minimum threshold for what "active" means for you.
In an open source community, the baseline could sound something like "we have 500 monthly active members, where a member is anyone who's opened at least one issue and therefore is in our Orbit 3." If the next month there are 550 monthly active members, we know the community has a 10% monthly growth rate.
Using the same logic as for community size, you can create a baseline for new members in a given time period. These are members who join and reach the minimum orbit level. An example baseline sounds like: "our community has been adding 25 new members per month, each of whom has met our milestone for being considered a member".
Unlike community size, the number of new members isn't influenced by existing members increasing or decreasing their activity.
With those baselines in place, the next step is to look at how many members the community is able to move from outer to inner orbit levels.
Let's assume that in the previous month, 25 community members moved up from Orbit 4 to Orbit 3. If that went well, we could imagine that adding 25 more members next month will be okay because, in effect, there are 25 new "slots" for new members to fill. However, if we add 25 more, and only 10 move up next month, we may have hit a bottleneck.
This analysis can be done between any 2 orbit levels to assess whether a level is ready to receive new members. Everything needs to move together.
Whether members remain at the levels they move up to is another important question. If they don't, it may also signal a lack of readiness at that level. This will be reflected in the community's gravity, which takes into account inward and outward movements.
This is how growth and gravity connect. The better the community is at moving members inward, the more space it will have to receive new members and to have members progress up.
In practice, this is true because communities are not audiences: they rely on person-to-person connections to function. Since a human being can only sustain and nurture so many connections, it's important that enough members move toward the inner circle to avoid those already there being overwhelmed with incoming members.
This is the delicate balance that a sustainable community must strike.