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It's good to look back to gain a perspective. This will give more concrete guidance moving forward.

Of course, that would be good to set a realistic goal that I can achieve only if I make an effort.

Too big a goal might bring frustration. Too small might not that motivating enough. Setting realistic goals to test our capacity will give us an idea to set even higher goals later if the former is achieved.

Exactly, it has to be balanced enough, so that it is not easy to achieve but not unattainable either.