As a pastor I must remind myself that I'm called to faithfulness, not success. Of course it is natural to earnestly hope for the movement of God to take place among the people you are preaching to. I want to see souls saved. I want to see revival. However, it is the Lord's perogative whatever visible results of ministry occur. To pine the visible results is only to allow pride, frustration, and envy to creep in. Then to take credit when visible results occur is to rob God of His glory. So lest I be tempted to make success my ambition rather than faithfulness I listen to the words of John Wesley who spoke with regards to the mystery of revival...
"We do not throughly understand the meaning of that word, 'The times and seasons God hath reserved in His own power.' Undoubtedly He has wise reasons for pouring out His Spirit at one time rather than another; but they lie abundantly too deep for human understanding to fathom."
From the Letters of John Wesley edited by John Telford; quoted in Wesley and Men Who Followed by Iain H. Murray (p 24).
"What then is Apollos? And what is Paul? Servants through whom you believed, even as the Lord gave opportunity to each one. I planted, Apollos watered, but God was causing the growth. So then neither the one who plants nor the one who waters is anything, but God who causes the growth." -Apostle Paul in 1 Corinthians 3:5-7