IME, managing runtimes. Not GP, but: Oh, JRE too old? Link to download the latest? Now it accepts the JRE, but the JRE refuses it with security errors. So you

IME, managing runtimes. Not GP, but: Oh, JRE too old? Link to download the latest? Now it accepts the JRE, but the JRE refuses it with security errors. So you turn those checks off and the jnlp runs but crashes with an obscure error. So you try another JRE until you find a version that works. While doing this, you interact with Oracle, at all times with the fear of their lawyers, until you decide to use a foss runtime. Now you are managing runtimes from different vendors with different configs and locations. Write once, troubleshoot everywhere.