The software doesn‘t do something that the product specification says it should do.
The software does something that the product specification says it shouldn‘t do.
The software does something that the product specification doesn‘t mention.
The software doesn‘t do something that the product specification doesn‘t mention but should.
The software is difficult to understand, hard to use, slow, orin the software tester‘s eyes will be viewed by the end user as just plain not right.
原文：http://www.cnblogs.com/viaiu/p/4806794.html