diff --git a/ocr b/ocr
index 07dc134..9f25402 100755
--- a/ocr
+++ b/ocr
@@ -77,19 +77,19 @@ class OCRWorkflow(WorkflowRunner):
 
     def workflow(self):
         ###
-        # Task "mkdir_job": create output directories
+        # Task "create_output_directories_job": create output directories
         # Dependencies: None
         ###
-        mkdir_jobs = []
-        mkdir_job_number = 0
+        create_output_directories_jobs = []
+        create_output_directories_job_number = 0
         for job in self.jobs:
-            mkdir_job_number += 1
+            create_output_directories_job_number += 1
             cmd = 'mkdir -p "%s"' % (os.path.join(job["output_dir"], "tmp"))
-            mkdir_jobs.append(self.addTask(label="mkdir_job_-_%i" % (mkdir_job_number), command=cmd))
+            create_output_directories_jobs.append(self.addTask(label="create_output_directories_job_-_%i" % (create_output_directories_job_number), command=cmd))
 
         ###
         # Task "split_job": split input file into one tiff file per page
-        # Dependencies: mkdir_jobs
+        # Dependencies: create_output_directories_jobs
         ###
         split_jobs = []
         split_job_number = 0
@@ -115,7 +115,7 @@ class OCRWorkflow(WorkflowRunner):
                     job["path"],
                     os.path.join(job["output_dir"], "tmp", "page")
                 )
-            split_jobs.append(self.addTask(label="split_job_-_%i" % (split_job_number), command=cmd, dependencies=mkdir_jobs))
+            split_jobs.append(self.addTask(label="split_job_-_%i" % (split_job_number), command=cmd, dependencies=create_output_directories_jobs))
 
         ###
         # Task "ocropus_nlbin_job": binarize tiff files from previous split