I lucked out because I researched before I started my first tank, and talked to a bunch of experienced fish tank owners, as well as my favorite lfs store, who set me up and was willing to test my water and also give me tips while waiting for my tank to cycle. Because of that I had a successful cycle and didn't lose any fish. Problem is if you do a fish in cycle there is only certain fish that can handle it. Espei Rasboras especially can handle anything, but then you get those who go to the store and get neon tetras, cories, or shrimp and don't realize that those guys have to go into a much more established tank.
Although I know my tank is cycled I won't be adding any more fish until I have gotten consistent reading on my nitrates for at least 2 weeks, then I will add more 3 more espies, and then wait until at least 6 weeks to add shrimp or pygmy cories, that way it will also give my time to grow some foreground plants for my cherry shrimp.