They are independent because they are not affiliated with the producer nor the user of the item being tested: no commercial bias is present.
Independent testing might have a variety of purposes, such as: There are various technical standards available which organizations can use to evaluate products and services.
International standards organizations also publish test methods: For example in software usage, the Capability Maturity Model Integration (CMMI) is a process improvement approach that “provides organizations with the essential elements of effective processes.” There are various levels attainable within CMMI, the highest of which is Level 5.
The Testing Maturity Model (TMM) has been designed to complement CMMI and is based on best industry practices.
The TMM has 2 components; firstly, a set of 5 levels that define testing capability covering maturity goals, subgoals and activities, tasks and responsibilities and secondly, an assessment model consisting of a maturity questionnaire and an assessment procedure.