I've read that electroweak symmetry breaking occurred "at a picosecond or so" after the Big Bang (in [a source I found](http://delphiwww.cern.ch/talks/general/Treille.tianjin2012/origin_tianjin_corr_reduced.pdf)).

I can't help wondering why it took so long to get started. For instance, was something missing up until then, which was needed by the [Higgs mechanism](http://en.wikipedia.org/wiki/Higgs_mechanism)?

What feature(s) of the Higgs mechanism, or perhaps what other theoretical consideration(s), was/were seemingly responsible for this very brief delay?