Setting a single goal, for example, running under the 4 hours for your upcoming marathon or having an excellent outcome for a meeting, make your life difficult. What happens if the conversation goes in a completely different direction or if there is a lot of wind during your run? You failed. You are still on step one and can start over again.
Minimal and Maximal goals
If you set two similar goals, you just doubled your chances on failure. Therefore you should not consider equal objectives. You should consider a minimal goal (simple, achievable, but still a step forward) and a maximum goal (can be utopian, a big bet or just your ideal solution).
How it makes life easy
Having a minimal and maximum goal creates bandwidth in between, which you can navigate. Your minimal goal should be entirely in your control, or you should at least be able to influence it. For example:
Minimal goal: I want to maintain our relationship and learn more about the other person
Maximum goal: I close this deal and open the door for after-sales.
Minimal goal: I want to maintain a good running technique, especially in the last 10k.
Maximum goal: I will run this marathon below 4 hours.
Set yourself up for success
If your minimal goal is a stepping stone for your maximum goal, you help yourself move in the direction you want to go. You could set your minimal goal as a smaller version of your maximum goal (e.g. I run the half-marathon in 2 hours). However, do not make your minimal goal a stretch already since it might only create frustration that you did not reach either of your goals.
You do not have to achieve the minimal AND the maximum goal. Achieving one of them is good progress. And as long you are progressing, you are growing.