Part of the process of learning how to garden and grow things is all about trial and error. Sometimes plants die on you. I try to do my research on soil conditions and strategically placing them in the most optimal spot of the yard, but some things are unforeseen like one plant thrives and grows so big it takes the sun from smaller struggling plant. Then the transplanting process is another hurdle. I've killed a few, but some are in revival mode like this purple shamrock or hydrangea that is now the size of a straw (major progress).