Having high expectations isn't all bad. There is evidence that having high expectations could be beneficial, whether it's boosting your productivity or realising your goals.

Is expectation a good thing?

Studies show that it's actually good to have high expectations when it comes to your relationship. It's healthy to have expectations of respect, affection, intimacy, time together, etc. ... It's good to have expectations. It's your decision what to do if your expectations aren't met.

Why having expectations is bad?

Unmet expectations about the past create regret, grief, sorrow, shame and sadness. Projected unmet expectations about the future create depression, anxiety, feelings of inadequacy, impatience and hopelessness. If you didn't have expectations, you would simply take things as they came and deal with them.