In this poem, the poet is talking about taking the wrong decision which he took in the past. According to him, he was quite curious to climb a mountain and hence he climbed on a hill with great difficulty (staggered). He finally managed to reach the top.
However, things went wrong. He had to struggle for breathing as there is low oxygen on the top. He got very ill.
He begins to regret his decision. According to him, he should not have made his curiosity make him take such a big risk. Rather, he should have set his goal on rather a smaller (low) area on that hill.
There he would have called the Samaritans (helpers) who would have told him to stop and not climb further. This would have saved him from falling in such a dangerous and perhaps fatal situation.
The poem seems to be deep and symbolic. The curiosity to climb a high hill probably means taking a big decision in life without knowing about the outcomes.
Sometimes we start thinking of doing something which we are not very aware of. And finally, fail badly which can prove disastrous for life.
The poet suggests that one should set goals which he is well aware of and there should be people around us who would guide us and warn us about the outcomes of our decisions.