In both of these countries there are Ryanair style trains. They’re green in the first country, blue and pink in the second.
In the first they’re run by a completely separate firm, and are run when people most want them.
In the second country they’re run by the same firm as the regular high speed trains - this means some hours you get a regular one and some hours the Ryanair style one, with no logic as to which you’ll get.