Holding shares in a professional or investment corporation which has unsigned resolutions (for dividends, etc.) and no other directors who can sign them.
It’s difficult to do post-mortem tax planning for corporate holdings.
Having outstanding tax returns for you or your spouse.
If there are significant tax liabilities, your estate will need to file the returns under the voluntary disclosure provisions to avoid late filing penalties of 17%.
Holding cash, investments, or GICs at a number of financial institutions.
This becomes a real burden for your executor, who must account for and recover the assets. This may also involve legal counsel and additional professional fees.
Holding investments in share certificate form.
These may be lost and have to be replaced, which will result in delays and additional fees in dealing with the assets.
Writing a will that does not provide adequate assets or support for your dependents, including your spouse.
A court order can override this, and will result in delays, additional professional fees, and complexity.