Glory
If you do your job right, pay attention to all the details, carefully interview witnesses, and follow the evidence where it leads you, chances are good that you'll figure out the cause of the horrible situation you're investigating. Sometimes, that means figuring out what is to blame and protecting from it in the future.
Occasionally, that means catching an arsonist, pyromaniac, or even someone who builds explosives. If you don't think catching a terrorist is glorious, ask someone who's done it before. You'll use your skills to find evidence and come to conclusions, and hopefully find the clown or the cause that's responsible for it.
Those who work with fire and police departments on behalf of the people of the community will be providing a valuable civil service. Those who work for insurance companies will save their employers a lot of money uncovering fraud, which will hopefully lead to some decent Employee of the Month recognition.
Inspectors who are active in certain organizations might even get a neat award for the trophy case. You're pretty much guaranteed some sort of exciting glory-filled moment―even if there isn't a sweet soundtrack in the background helping you investigate.