diff --git a/Makefile b/Makefile
index df26c26a9..2610afac7 100644
--- a/Makefile
+++ b/Makefile
@@ -333,7 +333,7 @@ start-%: --develop
 	echo "DEV $(DEVELOP)"
 	if [[ "$(SINGLETON)" = "true" ]]; then \
 	  CONTAINER_FILE=$(DEVELOP)/$* ; \
-	  if ! [[ -e $${CONTAINER_FILE} ]]; then \
+	  if [[ -e $${CONTAINER_FILE} ]]; then \
 	    >&2 echo "Another $* service is already running! Use \"make new-develop\" or \"make start\" to start a new develop instance despite currently running services." ; \
 		exit 1 ; \
 	  fi \