This

src/main/java/com/intellectualcrafters/plot/commands/SetOwner.java

@@ -101,13 +101,13 @@ public class SetOwner extends SubCommand {
         }
         
         final String world = loc.getWorld();
+        final UUID uuid = getUUID(args[0]);
+        if (uuid == null) {
+            MainUtil.sendMessage(plr, C.INVALID_PLAYER, args[0]);
+            return false;
+        }
         for (final PlotId id : plots) {
             final Plot current = PS.get().getPlots(world).get(id);
-            final UUID uuid = getUUID(args[0]);
-            if (uuid == null) {
-                MainUtil.sendMessage(plr, C.INVALID_PLAYER, args[0]);
-                return false;
-            }
             current.owner = uuid;
             PS.get().updatePlot(current);
             DBFunc.setOwner(current, current.owner);

src/main/java/com/intellectualcrafters/plot/commands/Visit.java

@@ -45,6 +45,12 @@ import com.plotsquared.general.commands.CommandDeclaration;
 )
 public class Visit extends SubCommand {
 
+    public Visit() {
+        requiredArguments = new Argument[] {
+                Argument.String
+        };
+    }
+    
     public List<Plot> getPlots(final UUID uuid) {
         final List<Plot> plots = new ArrayList<>();
         for (final Plot p : PS.get().getPlots()) {

src/main/java/com/intellectualcrafters/plot/object/PlotAnalysis.java

@@ -386,7 +386,7 @@ public class PlotAnalysis {
     }
     
     public static void logln(Object obj) {
-        System.out.println(log(obj));
+        PS.debug(log(obj));
     }
     
     public static String log(Object obj) {