Unix is for thee, if...
Thou wantest to fully control everything thou dost even if that meaneth that thou sometimes must control something that seemeth not necessary to control.
Thou likest to learn.
Thou preferrest to spend a lot of time learning some powerful tool and then save much more time using this tool, rather than wasting thy time using less powerful tools.
Thou wantest a system that breaketh without a reason not.
Thou wantest to be able to see anything that happeneth inside the system.
Thou art a programmer or just likest programming.
Thou likest freedom and hatest the very idea of deceiving and controlling others.
Thou believest that reinventing the wheel is a very stupid thing to do.
Thou likest to play with software, configure it, plug different things together.
Thou wantest simple tasks to be simple to do, and wantest to automate everything that is possible to automate.
Thou likest free and open source software.
Thou likest small but powerful programs.
Thou likest portable software.
Unix is not for thee, if...
Thou wantest not to control anything that is not necessary to control, even if thou loose a lot of power.
Thou likest to learn not.
Thou wantest tools to be as simple to use as possible, even if that meaneth that they will be slow and somewhat defective.
Thou wantest not to know about anything that happeneth inside the system, except when thou really must know about it.
Somebody tried to explain basics of programming to thee, but thou couldst not even begin to understand it. Neither thou wanted to.
Thou carest not about taking away somebody's freedom.
Thou seest nothing bad in having only one way to do something.
Thou hatest to configure something, thou wantest everything to work right away.
Thou mindest not to spend a lot of time doing some stupid simple work like typing a lot of similar text fragments.
Thou likest big powerful programs and mindest not them being commercial ones.
Thou mindest not if the program is not portable as long as it runneth everywhere thou wantest it to.
Thou wantest everything in thy system to be in thy native language, even debugging messages in English annoy thee.
Note that it is not exhaustive list, neither it is some logically selected sub-list - just random thoughts.