If it’s not broken, don’t fix it
The Chelsea team has yet to lose a game in the Premier League this season and are already looking like the team to win the league. They have also qualified for the knockout round of the UEFA Champions league and are one of the teams expected to challenge for the European Cup as well.
They are going great guns and bringing in a player from another league, midway through the season might be more disharmonious than expected. Chelsea have a tight unit who don’t need any more players to come in, too much of something can also be a bad thing. Reus doesn’t need Chelsea and Chelsea do not need Reus.
Marco still needs time to recover from his injuries
Marco has had a pretty poor time regarding injuries ever since the start of the World Cup, he injured his ankle in a pre-world cup friendly and was not able to take part in the World Cup, which Germany won. He has had a couple of injuries in the league already this season and has missed quite a few games for Borussia Dortmund.
Reus should stay at Dortmund at least until he feels a 100%, instead of moving to Chelsea so early, it could be detrimental to his fitness of course he would have Eva Carneiro as his physio but that wouldn’t ensure he gets back to full fitness.
Reus is a talent which would be better suited to clubs like Liverpool or Arsenal who need to have quality wide men and don’t have them in their squad, Chelsea are strong as it is and getting Reus in wouldn’t be the best option for Reus.