When you draft a will with your attorney, there are a few things you might think that you want to include. However, there are times when including your wishes isn't appropriate.
For example, most people think that a will is where funeral instructions should go. The truth is that your funeral instructions should not be in the will, because the settling of the estate won't happen until after the funeral. That would mean that any instructions you left couldn't be read until after the funeral. To avoid this, you can make a separate document that states what you want to have happen at the funeral. Talk to those around you about you want, too, so there are no surprises.
Another thing you shouldn't put in a will is any kind of gift that you intend to be used for illegal purposes. While that seems obvious, people have done it. For example, you shouldn't say you're leaving your vehicle to your son so long as he transports marijuana to your friend. Similarly, you couldn't ask for property to be used for illegal purposes.
When it comes to conditions like in the above paragraph, remember that they're not all legal. Conditions like requiring marriage, change of religion or divorce are not legal. The court won't enforce them, and the beneficiaries will obtain the assets regardless of your wishes.
These are a few things to leave out of your will. There are better alternatives to use for your final wishes and better ways to leave behind assets with conditions than to do so in your will.