why not just decrease turn times?

Actually, I agreee with Vampiero completely. Some people do this intentionally - maybe they hope someone will not finilize and they will take advantage, maybe they believe it gives them an edge (by annoying everyone else), maybe they are unhappy with how the game is going and this is some form of a protest :)
There's no reasonable explanation when you have 2 or 3 people in a game - all finilizing their moves half an hour before the deadline (or just not bothering to press the Finalize button at all) - and this is every turn :)

And, it is pretty easy to see when did someone actually log in - so you know if time is the problem :)

My suggestion - if the game allows it attack them - and explain they should finilize earlier. It actually works very well :)
Will work even better if more people did it :)

Maybe, a person just likes to have consistent deadlines. By not finalizing, the deadline remains relatively the same throughout the course of the game.

Sometimes my schedule rather harshly restricts my login times, and by not finalizing I can be sure not to miss any turns, as I have to login at about the same time every day. I also believe that not finalizing can be an effective, and completely fair, tactic. There was one memorable game where I managed to drag out the fall of my decaying empire long enough to bore the 2 others into a draw.

Well as a habitual non-finalizer... I have to say I'm quite affronted by how affronted people get when I don't finalize...

Finalization was not designed to be the norm, but the exception, for when all players were ready to move on to the next phase before the 24 hours were up. Otherwise, the game would have consistent 24 hour phases. Especially now that phase length can be set at game creation...

Honestly, it's not unethical at all to not finalize. It's not meant as a tactic to annoy other players... I always expected a little more patience from Diplomacy players... especially considering Diplomacy has a long history of MUCH longer phase lengths during postal and play-by-email games.

There are many reasonable explanations to not finalizing and letting the 24 hours run on. It's been dismissed earlier enough as if it was not reasonable, but waiting for last minute press and negotiation is important. As not everyone shares the same timezone and login times, it's important not to finalize your orders before letting all players have their say. Log in times don't necessarily show whether time is the problem. I often log in when I have a spare second just to check my game statuses, and see how much time I have left and to check any new press. I don't always have time to reply adequately or decide orders, and I often have to log off right after. The time off lets me think more about what I'm going to do, and I'm thinking that many players don't put enough thought into their games, when they could be enjoying an entirely new level of depth.

As it's also been mentioned, there are times when I can't be sure I can get on more than once every 24 hours and prefer a more or less static deadline. In this case, not finalizing "ruins" the game a lot less than missing individual phases. Understand not everyone has the same amount of time on a computer that you might enjoy, and you should certainly not punish them for it or suspect that they have malicious intent behind their lack of finalizing.

All I ask is for a little patience and understanding... Even when the "offending" players are down to their last few SC's, it's much more important that they not give up and lay over than it is that you get to punch in your orders a little earlier again. There is no race going on here...

I always finalise, and have raised this b4 only to be blasted...

i guess thats why there are shorter turn games now.

Also some players deliberately do not finalise as revenge, or if they are losing...
Not good, but not illegal either.

Absolutely not! I will use every minute of the time allotment if it pleases me. If you aren't willing to wait 24 hours for a turn to end, don't join a game with 24 hour turns...

People have lives outside of phpdip and a consistent deadline is convenient.

If you want faster games, reduce the time per phase.

Never finalise early - you never know which player might miss a go. Check their last log in times, and if they haven't logged in since the last turn, then take advantage. Think of it as if a General's orders went astray in transit from the rear to the front lines...

I don't have a problem with some people not finalizing, but there is a significant portion of our players who start dragging out games as soon as they are losing. Like Vampiero said, they play at one rate up until they're at a significant disadvantage and then they let turns run out.

If they were using this extra time to petition for help or whatever I could understand it; but from the lack of response I usually get in these cases it seems obvious that there is no discussion happening. It's really just a case of sour grapes.

Some people do that because they are going into CD and just abandoning the game. THAT bugs me. Maybe there should be a button to switch your country into CD automatically for exactly this purpose?

I agree completely with Chrispminis. In fact, I have at times wished that people couldn't finalize... because if there is a retreat or build phase where I don't get to build or retreat, then my whole schedule gets shifted by 12 hours sometimes, making things quite inconvenient.

In fact, that might be a different topic altogether... would it be possible to implement a standard 24 (or 12 or whatever) turn cycle for a game that isn't changed by everyone finalizing moves? That way a game to maintain a sense of consistency. Not as default of course, but as an option when creating the game.

If we keep making so many options then soon the game creation menu would keep you scrolling down and down and down...

Wait... So if I don't hit finalize the orders I have set up will automatically execute when the deadline is up? I had been under the impression that I had to finalize sometime before or at the deadline, or my orders would simply not be submitted. Was I wrong on that? Can I enter a bunch of moves but not hit "finalize" and then still have them execute when the deadline comes up?

Yes, you can.

Oh, huh, well most of the time I'd rather finalize and get on with the game but that could definitely be useful sometimes if I know I'll only have a certain time to be available on a given day, or want a consistent deadline for a while (for example if I go on vacation and have limited internet access).

I disagree, I am sometimes entirely sure of my moves yet I do not think i can be back in the next 24 hours but more like 30 hours, so i let it time out, i like to keep it cyclical at certain times of day to be sure I will be back before the next turn ends.