Drupal has this problem, and has tried to counter this fact with:

- novice tags for bugs [1] - mentions on your project bio page detailing how many contributions you have on drupal projects in the past three monts (even if it was only rolling a patch or commenting, if your name is just mentioned in the commit, you don't need to be the author) [2] - and a lot of documentation on getting started [3]

And Dries (the creator of drupal) touch this same topic (comparing open source with the commons) in a 2014 DrupalCon keynote): https://youtu.be/4NN5EM4CYVE?t=10m45s

[1] https://www.drupal.org/project/issues/search?status[0]=1&sta... [2] https://www.drupal.org/u/catch [3] https://www.drupal.org/contributor-tasks https://www.drupal.org/getting-involved