Pretty great tradeoff if you consider (in case of Poland) 26 vacation days, up to 180 days of sick leave with 80% of wage, 20 weeks of maternity leave, having the employer respect the same notice period.

Ignoring fact that you can't be "just" fired without any reason - it must be result of your performance, behavior, or position reduction. Employer who would fire anyone just because of a bad mood, then hire somebody else next day as a replacement, will simply loose in court.

And 3 months notice period is for employers with 3+ years in company, others have 2 weeks or 1 month.