Isn't it good to have some expectations? Especially if one wants it to go somewhere.
Of course, but you have to have different expectations in the beginning. Expect to be treated with respect. Expect that they will end things once they figure out that you aren't a good match, instead of stringing you along and wasting your time.
In the beginning, it's about getting to know one another, building intimacy and feeling chemistry. I look for long term. It's what I want, but you have to learn about a person to see if they are someone you want to be in a long-term relationship with. For those being authentic from day one, I can usually figure that out in about 6 months. I know if they are long term for me and I usually know if they aren't marriage material for me in that time. (I can absolutely spend my life with someone I'll never marry.) If someone isn't being their true self yet, because most people put their best foot forward, so to speak, it may take longer to see who they really are.
I've gone on so many dates. You can chat with a person, and feel like you are connecting well, and like everything they present, and then there's no chemistry. I've dated these types of connections longer BECAUSE they were great people. I enjoyed my time with them and wanted to see if something would develop, but sadly, it didn't and I had to move on. I need chemistry. I need that chemical that drives me to WANT to spend time with that person, to want to talk to them daily and grow that deeper connection. Without it, the "getting to know you" process is so much effort and work that I don't desire.
Other times it takes a little more time to figure out if certain connections are actually good or not. You cannot expect that just because someone wants long term that they will start that from day one. It doesn't work that way.
For me, it's incredibly rare to find someone I'm attracted to who also has a personality, values and philosophies that work with mine. I've gone out on 100 first dates and less than 5% made it to a second date. Even less made it further than that and only 1 has ever been marriage material for me. And think of the 1000's of people I see monthly and have no interest in dating at all.
It takes BOTH people feeling something and wanting to learn more to keep things going. Once one of them is no longer interested, it's over. Add poly, practicing your kind of poly, where your needs and availability match theirs, where each of your life situations work together, etc., and it gets harder and harder to find the right one(s). Sometimes it takes years to find that person, and it's worth it.
So don't get rid of your expectations, just change them. Expect to meet some interesting people along the way. Expect to have some amazing dates and some bad ones. Expect it will take time to find the right people for you. And have no expectations of anything being long term on the first date or any number of dates. Long term is achieved by actually continuing to date, not the desire for long term. You shouldn't want long term from anyone willing to do it. You should want long term from the people who want to keep dating you and you also want to keep dating.