i would say what type of detective, there are many
the police
Criminal profiler
etc
Regardless you do different things and specialize, although the average case take a while or go cold (some are just poorly approached, their are crooked cops) It doesn't mean it will define you in the field if you are passionate. Some detectives come in and notice what others don't (just like on tv) and solve the cases. There are numerous renowned criminal profilers that came in and solve the cases, it is usually getting the suspect, forensics, judicial system, etc that take the most time. Sometime it take a long time to just get a lead. Be patient and keep striving to achieve your goals, there has to be an exception to every rule