It's all down to different cultures. Open Source projects, the way they currently are, are driven by coders - version control, bugtrackers, IRC etc - all geeky things.
Designers work in different environments: personal discussions, meetings, illustrator, photoshop, other web communities (like dribble and obscure sections at flickr).
If you ask a designer to add stuff to your repository, you're asking him to adapt to your way. Most designers aren't going to learn git.
To embrace designers means that you include them in your processes and tools. And let them in on strategic discussions - that's where good design is most often lacking in OSS.
If you continue with a Codeocracy where only check-ins are valued and the guy with 100k lines of written code is king, you're not going to convince many designers to help you with their free time.
Designers work in different environments: personal discussions, meetings, illustrator, photoshop, other web communities (like dribble and obscure sections at flickr).
If you ask a designer to add stuff to your repository, you're asking him to adapt to your way. Most designers aren't going to learn git.
To embrace designers means that you include them in your processes and tools. And let them in on strategic discussions - that's where good design is most often lacking in OSS.
If you continue with a Codeocracy where only check-ins are valued and the guy with 100k lines of written code is king, you're not going to convince many designers to help you with their free time.