We all minister with mixed motives. It is important to be aware of that, and to prayerfully stay before the only One who can really know what is going on inside of us. Sometimes it can be helpful to delineate some of the unhelpful or sinful motivations that can sabotage a ministry. It is not possible to avoid every negative motive all the time, but we must beware lest any of these start to fester within and then characterise our ministry.
1. Preaching to impress. The inner child may not be as gone as we think, and it can so easily creep out and we then start to show off.
2. Preaching to be liked. The insecure self can manifest in public ministry and we can start to crave affirmation.
3. Preaching to be needed. The shepherds of a flock do make a difference to the lives of the sheep, but something is off if the need to be needed starts to grow. You are replaceable.
4. Preaching to validate our worth. The unsettled soul can seek validation for our education, our calling, our sense of identity, etc., through the medium of ministry. If your worth is not firmly rooted in Christ (as just you, minus all trappings of ministry position), then you have a problem and you may well become a problem.
5. Preaching to control behaviour. This may be more common than we think. Instead of patient ministry trusting God’s Word and God’s Spirit, we can shortcut the process and start to pressure conformity in our listeners. Quite simply, our life is easier if they will just behave like Christians.
6. Preaching to build a mini-kingdom. Again, too common to count, and probably involves a combination of the above issues … but it happens when we preach in order to have a little empire where our influence, our voice, our significance, and our ego get propped up.
7. Preaching to be paid. It is absolutely appropriate that churches recompense preachers and do so properly. It is shocking the way some churches do not care for their preachers. However, if I am preaching in order to get the paycheck, then my ministry motivation is broken.
8. Preaching because it is all I can do. The fires within will not always burn bright in perpetual personal revival. At the same time, if the fire has really gone out, please don’t just preach because you have no option. You do. Trust God, ask others for help, and choose not to preach until you can stand with a fire for Him again. By faith hold back from doing damage and trust God to carry you through it.
There are plenty of other mis-motives that could be listed. What have you seen in others (no names please), or in yourself?
Biblical Preaching 
Preaching way over your allotted time and way past the comfort zone of the people, ignoring the signals from the other leaders to “land the plane” because “I put so many hours into preparing this, so they’ll just have to sit there until I’m finished – I’m not going to shorten it” Thats selfish too
Related to Gary’s comment above, another disservice we preachers do to hearers is simply refusing to edit out a story, or a direction, just because we like it, or we put a lot of time into shaping it. Preach one sermon, and then say “amen.” Don’t feel like you have to show all of your work. This isn’t geometry. Also, and hopefully this goes without saying, but making yourself the hero of your sermons. (Probably a correlary to “preaching to impress” and “preaching to be liked.”)
Thank you. This is a great article. I backed into it from an image search, of all things.