The main problem I always found with parents evening was that the parents you really wanted to see never turned up. If pressed, they would always have some excuse which was usually incomprehensible "Sally weren't right and the bus didn't stop on the way back an' 'ow am I supposed to know... blah"
Another problem was that many teachers tried desperately to be positive about the pupil "Kaylee would work really well if we could just get her to stop texting the layabouts who hang around the school gates..." and only told the parent good things; so when they got to me, they were unprepared for the truth and simply wrote it off as the rantings of a madman.
Some schools even give the kids a day off and have 'Parents Day' for no obvious reason, other to presumably make it harder for parents with jobs to attend. Amazingly, at other schools; parents don't even get to see their child's teachers, they just listen to a report read to them by the form teacher; which is an utter waste of time. Surprisingly few parents complain- I'd hit the roof.
Most parents never really had much of a clue about what they wanted or why they were there, as this report suggests. The ones that were clued up always took me by surprise. Best of all is when you mix up a child with another one who has a similar name and tell the parents how well they are doing before realising they were expelled last month.