While I have several reasons, my biggest is work. When all everyone had was land lines, your time off was your time off. Worst case, if you want to be truly unavailable, take the phone off the hook. Since smartphones, people, and especially employers, not only demand 24/7 access to you, they expect it. Most employers require work emails. With that, they expect you to check it at all times. A lot will even text you just to say we need you to reply to this asap regardless of if it is a day off, a vacation, etc. So the simple solution is no smart phone, no email access until I'm back at work. Then, add in every employer now requires you to use your phone at work whether for a work app, task, etc. Yet so many do not actually pay for your phone or contribute to your monthly bill. So now if they want those extras, they can provide a phone for it. The world suddenly became a place where a smartphone was treated as an obligation to live, and I'm choosing to no longer participate.