A devotee should give up enthusiasm for big endeavors in three situations.
If the person has no funds in the beginning, he should not attempt the work.
If his life is nearly finished, he should not start a big project.
And if the work requires a lot of manpower and he has no way of getting assistance, then he should not attempt the work.
Such things create obstacles in devotion. If huge projects for a temple, hall, or ashram are difficult to execute, then they should not be completed.
Sri Caitanya-siksamrita, by Bhaktivinoda Thakur