Whilst I am not a fan of the logging pain in java, not invented here would apply to anyone thats not log4j since they were really the first to get properly started.
The creator of slf4j and logback originally created log4j, so "Not Invented Here" is literally not true as the inventor invented those three libraries.
Nobody cares who was first. The right thing to do would have been to focus on getting j.u.l right and then be a grown-up about it and ditch log4j.
Apache fucked up and Sun fucked up. And we all lose.