Deciding where maintenance goes

We always have a debate on where software maintenance should be done. Is it better in a separate group or the developer maintains the software he builds for the rest of his life! Our second survey results look quite the same as the first one:

Cust. Sat: How do end-users feel when served by this group. Costs seem higher or lower with this model? Is it longer to be served by this group? How about the quality of the software over time.

Arguments Against                                Arguments for
Separate Maintenance                           Separate Maintenance
Cust. Sat: Users like the initial developers      Initially less happy
Costs:   Seem to cost less                            Seem to cost more
Delays:    Slow and impacts other projects     Perceived as Quicker
Quality:   Mostly in the developers head              Tend to be higher here
Size:          Good model for small shops            Better fit in big organizations
Posted in Software Maintenance.

I am full professor of Software Engineering at the University of Québec in Montréal, in its Software Engineering faculty. I have more than 30 years of Helthcare, Finance/Banking and Telecommunications IT industry experience, especially in Cloud Computing, Big Data, software acquisition, contracts, software quality assurance and business process management. I am more comfortable with open source, practical applications and technology transfer to industry.
Currently I concentrate on research projects. In the past I was the recipient of the ISO award for higher education in standardization in 2011, as well as the chair of the Software Engineering gratuate program and of the Software Engineering departement. I also published Software Engineering Books: Software Maintenance Improvement and Software Quality Assurance.