Nobody has mentioned PRIA (Pilot Records Improvement Act 1996).

If you're new to the airlines you need to understand that your training records follow you for the rest of your career. Why is that important? Every time you switch a job, you new employer will receive your training records from last employer.

Bust a checkride or need extra OE (operational experience) and it follows you for the rest of your career. It may not be a deal breaker but it's something to be aware of.