1. Senior engineer productivity
Most companies have zero idea what to do with a senior engineer and they measure them against a junior engineer. The junior engineer usually does the following:
- works a tonne of hours - closes a tonne of bugs - makes a tonne of mistakes - asks a tonne of questions - uses up a tonne of senior engineer(s) time
And you end up with:
- a high ticket/bug fix rate per day from the junior - generally horrible and poorly designed code from the junior but the code works - few big fixes from the senior - what the senior does produce is generally better designed, fewer bugs and is easier to maintain.
If you have hired a quality senior engineer it shouldn't take too long before your junior and mid level engineers start soaking up the time of your senior engineer. It shouldn't take too long for your senior engineer to become the subject matter expert in several areas of your product which takes up even more time.
I am usually hired because things are a mess and they need to be cleaned up. Years of junior engineers doing the best they can with limited knowledge and experience tossed in with some management pressure leads to unmaintainable code/environments.
The largest impact I have ever had was when my manager put some trust in me, gave me autonomy and a huge project. I think this is what you should do with your senior engineers. Give them the space to make an impact.