code: public String getSkippedReason(Plugin plugin) {
          PluginStats pluginStats = mapPluginStats.get(plugin.getId());
          if (pluginStats == null) {
              return stopReason;
          }
          return pluginStats.getSkippedReason();
      }
docs: Gets the reason why the given plugin was skipped.
  
  @param plugin the plugin that will be checked
  @return the reason why the given plugin was skipped, might be {@code null} if not skipped or there's no reason
  @since 2.6.0
  @see #isSkipped(Plugin)