A disappointing combination of wooden acting, poor casting, slow story telling and a complete lack of classic 'heart' moments to connect the audience with the characters resulted in a wholly underwhelming and disappointing film.
This was always going to happen when you try and whizz through 7000 years of stories and 10 main characters and would have been much better suited to a wandering Disney+ series where each characters motivation and story could have been explored properly.
It's sad to say that the most exciting moment in the whole film is the second post credit scene- but the sooner we can get away from the eternals and on to some different Marvel characters, the better.