Why does my dad vape?

It is best not to smoke at all, but for those who can't overcome their addictions easily, e-cigs is a safer option than cigarettes. E-cigs don't give off-second hand smoke. Cigarettes contain tar, formaldehyde, hydrogen cyanide, arsenic, lead, ammonia, benzene, microscopic glass particles, nitrosamines, carbon monoxide, Polycyclic aromatic hydrocarbons (PAHs), and apparently some even contain radioactive elements like uranium according to the American Cancer Society.

E-cigs can contain some heavy metals like lead, but e-cigs don't have all the other stuff that cigarettes have, so while not being healthy - they are healthier than cigarettes by comparison. Note that Popcorn lung can develop from a chemical found in many e-cigarette flavors called diacetyl, so make sure to check the ingredients in the flavors to avoid this chemical. If you don't smoke, it's best to avoid it altogether. But if a person smokes cigarettes, then switching to vaping seems to be a better alternative (if someone can't give up on nicotine altogether). I've heard claims that e-cigs have helped people quit because they can go from higher doses of nicotine to lower doses, but of course this is not everyone.

For most people over the age of about 30, vaping is a less harmful alternative to smoking cigarettes. And something they switched to when trying to give up their addiction to tobacco.

For people in their teens and twenties, it's more what they did from the beginning.

There are a lot of chemicals that you can vape with you can even have vape juice that has no chemicals. Your father may be using nicotine vaping he may be using CBD vaping. The idea is to provide the delivery of a drug like nicotine without burning your lungs up with the smoke.

it's safer and usually less addicting than smoking cigs or drinking. there's also a fashion component to vaping since it's a relatively new fad.

it's a hobby on par with drinking coffee for the stimulating properties. nicotine is itself a mild stimulant (not to mention the smoke is flavored to taste good).

Addiction

Maybe he’s stressed

If he's vaping nicotine it's because he's hooked on nicotine.

why do people watch porn? or smoke?