diff --git a/app/services/group_stage_service.rb b/app/services/group_stage_service.rb
index 0c2b7d7..ea03168 100644
--- a/app/services/group_stage_service.rb
+++ b/app/services/group_stage_service.rb
@@ -4,22 +4,21 @@ class GroupStageService
   def self.generate_group_stage(groups)
     raise 'Cannot generate group stage without groups' if groups.length.zero?
 
-    average_group_size = (groups.flatten.length.to_f / groups.length.to_f)
-    raise 'Groups need to be equal size' unless (average_group_size % 1).zero?
+    # raise an error if the average group size is not a whole number
+    raise 'Groups need to be equal size' unless (groups.flatten.length.to_f / groups.length.to_f % 1).zero?
 
     groups = groups.map(&method(:get_group_object_from))
     Stage.new level: -1, groups: groups
   end
 
   def self.get_group_object_from(team_array)
-    matches = generate_all_matches_between team_array
-    Group.new matches: matches
+    Group.new matches: generate_all_matches_between(team_array)
   end
 
   def self.generate_all_matches_between(teams)
     matches = []
-    matchups = teams.combination(2).to_a
-    matchups.each_with_index do |matchup, i|
+    teams.combination(2).to_a # = matchups
+         .each_with_index do |matchup, i|
       match = Match.new state: :not_started,
                         position: i,
                         match_scores: [