One shouldn't have to use tools to fix problems that could have been avoided in the first place.
As someone who bought his first Mac over 29 years ago and still uses some of the FileMaker files created then, I find that statement ridiculous.
Systems need updating, incompatibilities need to be found and weeded out. That's just part of being a longtime user.
Finding that old Big Fish Audio plugs, 2005 HP applications, Finale 2009 Help files, CD Spin Dr. and the Bresink crap are gumming up the works in 10.8.2 (but worked great in 10.6.

is part of moving forward. I have watched the Mackie HUI drivers try to load in DP 8 after a plugin install or OS update and have seen DP 7 fail to find plugins. If you want to do a clean install, I won't stop you but I can fix any of those problems in less than 5 minutes. Except for the DP issues, they stay fixed.
There's no magic way to devine these things. Understanding crash reports, console and the DP Background Processing window, OTOH, gets these things discovered and fixed right away. Why spend hours or days when you can find the problem in minutes? Even if you don't know the answer, finding the problem is 3/4 the way there. Google it and, often as not the answer will show up.
Yes, in each case, a clean install would have fixed it –
as long as I didn't reinstall any of the above but, for me, that takes days in my spare time. I still have to make a living on my Mac and can't afford the luxury to waste that kind of time.
In the Classic MacOS days, clean installs were definitely the way to go. No doubt about that. I used to get crashed clients back up and running very quickly with a clean install, back in OS7, 8 or 9.
Those were the days, yes. On my own system. I did it in 6.7 on my Plus when my first HD crashed and 8.0 when I got my Beige G3. The other 30 or so Macs that I take care of, yea, it was something I did.
OS 10.5 and Time Machine meant never having to do that again except for once on my own iMac last October – and that was a choice I made, not something I had to do.
I did my own system again when there was a Time Machine restore bug in 10.9.4. I was doing some testing for one of my clients and realized it had been 16 years. So, even though I could have popped the TM drive into my eSATA dock, I did it to lighten the load on my hard drive before I installed my new SSD. The bug was fixed in 10.9.5, BTW.
If you want to shout to the rooftops why you believe in clean installs to fix simple problems, knock yourself out. If other people let you waste their time, not my issue. If you think there are two sides to this, I am not playing that game.
Some of us are hobbyists. Others of us use these PCs and Macs in our work. Again
Back to the OP. You can activate DP's Background Processing window in Preferences. Either it or Console (sometimes both) should tell you where the problem lies.
DP 8 has this thing where faulty processes will attempt to load three times before DP gives up and loads the rest of the program. This can show up in either window. The usual fix is to reinstall DP 8 over itself. Sometimes you also have to trash the Preference files but that is rare.