I never had any experience with polyamory before going into this relationship... sure, I've been in "easy/open" relationships, but this was a huge experiment for all of us. If you never had such a relationship, you might be along the same line of though... so hey, lets compare!
Starting this, I thought something like:
"Oh we will all be perfect lovers/friends and share our happiness."
"I will not get hurt by being cheated on or lied to."
"I will have the possibility to find others, should I desire so."
"So much kinky sex!"
Soon however, these ideas clash with reality... and while they still work, it just takes serious effort... being poly is hard! Just as every other kind of relationship...
"We have to compromise, share our time and sometimes have to fight for our "me" time. We do not all think equally about all subjects and have to make deals."
"Stating the truth of what you feel is painful, hearing the truth about certain things can be painful, too"
"We have to face the reality of our partners choices or wishes for others and discuss and deal with them."
"We have to respect the physical limitations and needs of all our partners and their partners"
As you see, it is not easy, in fact it is bitching hard to compromise and admit things... but do you see the other thing? I wasn't intentionally writing so, but you can see I am talking about "we" or "us" facing these problemes... and if I think back, each troubled moment I had, I also faced with the support and will of my loved ones, who wanted it to work, just as much as I did. And we did make it work and I am certain we have the capacity to overcome all problems.
What I am trying to tell you reader is that, yes, relationships are hard and yes, being poly has its very own difficulty, but with each problem you overcome, you grow stronger.
It is worth the effort.