Here Schopenhauer argues for a middle way between the present and the future.
SECTION 5. Another important element in the wise conduct of life is to preserve a proper proportion between our thought for the present and our thought for the future; in order not to spoil the one by paying over-great attention to the other.
Those who strive and hope and live only in the future, always looking ahead and impatiently anticipating what is coming, as something which will make them happy when they get it, are, in spite of their very clever airs, exactly like those donkeys one sees in Italy, whose pace may be hurried by fixing a stick on their heads with a wisp of hay at the end of it; this is always just in front of them, and they keep on trying to get it. Such people are in a constant state of illusion as to their whole existence; they go on living ad interim, until at last they die.
How exactly does this concern function? It seems that his concern is that one will miss a current benefit but fixing attention on the future. There would be a failure to enjoy some good currently in hand, in favor of a proposed good which may come into existence in the future.
The donkey staring at the carrot will never see the good things which pass him by, because he is fixed so intently upon the future.
As such, he is offering standard “good advice”. But there is a question here: how does his advice square with his philosophy. If the only true good is renunciation of the present and a desire not to obtain good but rather to avoid pain, a focus on the future to the exclusion of the present might be psychologically effective.
He also does not seem to considering the question of hope at this point: If I am sick and I have no hope of recovering, my relationship to my illness will be quite different than if I am sick an hope to soon recover. In fact, my recovery will be helped by my hope to recover.
A reward which will come at the end of a present effort will provide motivation to complete task. One would not perform the work without the promise of reward.
There seems to an inconsistency in his approach at this point. Yes, one could nuance the matter in a way that many systems do to avoid there most difficult inconsistencies. But Schopenhauer seems to see no inconsistency here.