Front

*Front:* Testing shows presence of defects

Back

can show defects, but not prove their absence

Front

*Front:* Exhaustive testing is impossible

Back

everything is impractical; focus on risk areas

Front

*Front:* Early testing

Back

testing early in the software development lifecycle

Front

*Front:* Defect clustering

Back

defects are found in a small number of modules

Front

*Front:* Pesticide paradox

Back

tests lose effectiveness; need to review and revise

Front

*Front:* Testing is context dependent

Back

approach varies based on the software context

Front

*Front:* Absence-of-errors fallacy

Back

no defects does not mean the software is usable