Well, they'll let you get away with it for years so they have a huge bill to jail you for. Quite often people trying this are either really poor and wouldn't owe much at all in taxes and maybe get money back or people with enough money to owe some money but too stupid to seek professional tax help to lower their liabilities. Really smart people and really dumb ones often get way more paid to them than they pay in income tax. CHOOSE WISELY, the IRS can and will jail you and take all your shit.