A: You know this concept inside out, but the complexity of multiple fully functional and integrated SharePoint farms might seem a bit daunting and, well frankly, expensive. Nonetheless, you need to consider multiple SharePoint farms simply because industry best practices and proper governance dictate separate development (DEV), quality assurance (QA) or user acceptance testing (UAT), and production (PROD) environments. Don't just think about customizations and Line Of Business applications; service packs and hotfixes must also go through a structured testing process, or you recklessly run the risk of corrupting your production environment and forcing an outage upon your end users.