Why do projects join the Apache Software Foundation?

While numerous open source projects operate on their own, others decide to join well-established foundations such as the Apache Software Foundation (ASF) and the Eclipse Foundation. Although many studies have investigated the motivations of individuals and companies contributing to open source, it remains unknown why projects decide to join software foundations. In this paper, we study the motivators behind the projects‘ decision to join the ASF, the geographical and organizational characteristics of these projects, and the differences between projects in terms of their motivations. To this aim, we analyzed 292 proposals submitted to ASF, and we found that there is an increasing number of company-based and Asia-based projects joining the ASF in recent years. Furthermore, we found that more than half of the projects are motivated by the desire to foster their community, strengthen the outcome of the project, increase interaction with other communities, and boost technical development. Our work shed some light on projects‘ expectations from the ASF. Having this understanding can help foundations to identify ways of supporting newly joined projects, while the prospective joiners can better decide on whether ASF is the right place for them by checking the alignment of their motivations and motivations of projects that have joined in the past. Open Source Software (OSS) is free to be used and modified by any-one in the world for any purpose. Nowadays, OSS is widely used in all kinds of products and hence plays an important role in our daily life. For example, as the most used OSS, the Linux kernel runs on 85% of all smartphones. To create a better environment for OSS de-velopers to collaborate and for OSS projects to grow, many software foundations have been established, such as the Apache Software Foundation (ASF). We have seen that many OSS projects joined the ASF over the years. To join the ASF, OSS projects have to donate all their assets to the foundation, adhering to the foundation's rules and culture. In this paper, we study why these projects decide to join the ASF to understand their expectations from such foundations so that the expected technical and non-technical support can be provided to them. We identified their motivations by analyzing 292 proposals that these projects submitted when applying for joining the ASF. We observed that more than half of the projects try to join the ASF with motivations related to fostering a community, strengthening the project's outcome, increasing interactions with other OSS projects in the ASF, and boosting technical development.