The relationship among software design quality, development effort, and governance practices is a traditional research problem. However, the extent to which consolidated results on this relationship remain valid for open source (OS) projects is an open research problem. An emerging body of literature contrasts the view of open source as an alternative to proprietary software and explains that there exists a continuum between closed and open source projects. This paper hypothesizes that as projects approach the OS end of the continuum, governance becomes less formal. In turn a less formal governance is hypothesized to require a higher-quality code as a means to facilitate coordination among developers by making the structure of code explicit and facilitate quality by removing the pressure of deadlines from contributors. However, a less formal governance is also hypothesized to increase development effort due to a more cumbersome coordination overhead. The verification of research hypotheses is based on empirical data from a sample of 75 major OS projects. Empirical evidence supports our hypotheses and suggests that software quality, mainly measured as coupling and inheritance, does not increase development effort, but represents an important managerial variable to implement the more open governance approach that characterizes OS projects which, in turn, increases development effort.

A quality degradation effect of proprietary code has been observed as a consequence of maintenance. This quality degradation effect, called entropy, is a cause for higher maintenance costs. In the Open Source context, the quality of code is a fundamental tenet of open software developers. As a consequence, the quality degradation principle measured by entropy cannot be assumed to be valid. The goal of the paper is to analyze the entropy of Open Source applications by measuring the evolution of maintenance costs over time. Analyses are based on cost data collected from a sample of 1251 Open Source application versions, compared with the costs estimated with a traditional model for proprietary software. Findings indicate that Open Source applications are less subject to entropy, have lower maintenance costs and also a lower need for maintenance interventions aimed at restoring quality. Finally, results show that a lower entropy is favored by greater functional simplicity.