Admittedly, my first days as a junior programmer were before some of you were born, but I'm thinking of a particular format here...
Learned as junior: If you report an OS bug or some other deep problem, seniors will not believe you and assume you're making excuses for your own bugs and lack of understanding.
Understood as senior: If a junior programmer tells me they found a system-level bug, I won't believe them and will tell them to go figure out what's wrong with their code.
Learned as junior: Legacy code is hard to read.
Understood as senior: Legacy code that I wrote myself is hard to read.
Learned as junior: Technical skills matter most.
Understood as senior: Communication skills matter most.
Learned as junior: New tech solves old problems.
Understood as senior: New tech creates new problems.
Learned as junior: If you report an OS bug or some other deep problem, seniors will not believe you and assume you're making excuses for your own bugs and lack of understanding.
Understood as senior: If a junior programmer tells me they found a system-level bug, I won't believe them and will tell them to go figure out what's wrong with their code.
Learned as junior: Legacy code is hard to read.
Understood as senior: Legacy code that I wrote myself is hard to read.
Learned as junior: Technical skills matter most.
Understood as senior: Communication skills matter most.
Learned as junior: New tech solves old problems.
Understood as senior: New tech creates new problems.