Written and posted back in 2015, this quote is very relevant:
▪ Your Harbaugh has been designed for offense and will require many high-end parts to run said offense. Yet his defense will be better than his offense. This paradox has not been explained.
I think this is very true which is why we were able to create a dominant defense right away but the offense is taking longer.
Here is the whole article for anyone who missed it the first time: