I am doing it for the reward.

[Aliatris]

I am sure that many times a PC has helped someone for the reward that would be given to him, not for helping others kindly.

As a reward of the quest the PC will get also hidden positive alignment points although he didn't care anything about the other, just for the reward, and his alignment this way would step a bit closer to the "good zone".

So does why I would suggest the creation of a new character mode.

Reward.
Config +reward. Config -reward.

By default it would be deactivated, when you active it, you are involving that whatever you are doing it you are doing now you are doing it for the reward or the loot (config +reward). This way you would never earn positive alignment points but you can still lose them and be each time more evil.

Of course you can return to a kindly mode (config -reward) each time do you feel good of heart and continue to earn positive alignment points when you deserve it.

[Dalvyn]

I think it is too easy to do a quest that is unrelated to your alignment then pretend that you did it "for the reward".

For SOME quests, the mob who gives out the quest immediately states what the reward will be. Those can be done "just for the reward". But when the mob does not state "I will reward you with this and that", there is no reason for anyone to do something opposed to their alignment. And just because the player knows that the reward is nice is not enough to make the character do it.

[Aliatris]

I agree with that, although there will be always situations in which it could be used.

[Selveem]

Too easily exploitable, really.

Think about all the people that "accidentally forgot" to turn it back off. This leaves them to always reap the best rewards without consequence IC to their alignment.

[Kelemvor]

In effect, evil characters already 'forget' to turn it on. Many many evil and neutral aligned characters have a hidden alignment approaching lawful good simply because they did not pass up the chance of a reward or glory/experience gain.

Some will argue that ICly their character would, just for kicks or because a job paid well. But here are a couple to think on...

Why would someone from Zhentil Keep take on a quest to learn about Chauntea in Shadowdale? The two cities are diametrically opposed and hostile. Not to mention that the faith is totally incompatible with the main religion of the city as well as most of its practices.

Why would an evil-aligned half-drow from Skullport go to incredible lengths to hide and sneak their way into Waterdeep merely to run errands for shopkeepers or learn about a religion

There is no physical reward from such a quest, no easily constructed IC reason why the character accepted and completed the quest... yet many have.

I suppose what I'm saying, is that characters (good or evil) should be responsible for their own alignments. If the reasoning is 'I just wanted the reward' and there is no reward mentioned or there is no physical reward on completion... then the option to avoid a drift either way is just an OOC means of gaining item/gloty/exp without losing alignment.

[Aliatris]

I didn't know that existed such problems related to quests/alignments, maybe it could be possible decrease the experience/kismet you get as long your hidden alignment each time differs more from your visible alignment, and this way get less.

Example:

A LE with a hidden alignment of LG will not earn neither xp or kismet.
A LG with a hidden alignment of LNl will earn half xp or kismet.