Prayer and preaching

Phil McAlmond writes about the need for prayer in preaching:

When I teach preaching, very often I find that those whom I am training are surprised by how much I stress the need for and the vitalness of a strong and dependent prayer life, even more so than a strong Word life. . . .

What I mean is . . . that if I simply study the Word of God and then simply preach what I have studied, it [is] very possible that what I am preaching is my own message and not the very Word of God for this time, place and congregation. Yes, it may be scripturally accurate exegesis but will it in spirit and truth be what the Lord is saying now, at this moment, to His people?

I've noticed a correlation between the amount of time I spend in prayer and the quality (if I may use such a term) of my preaching. Why then, I wonder, do I sometimes find myself working with too little prayer? I appreciate Phil's reminder.