The first few days, the hardest ones, every single thing that happens to you (had a bad day, stranger frowned at me, stubbed my toe) is weighed and a decision is made. For a seasoned addict, many of these events have the automated response of ingesting your drug of choice.
Anecdote: I've quit smoking and any form of nicotine 3.5 years ago. I don't miss it. I have not relapsed once. Yet to this day, there are moments where I catch myself feeling that something is missing. That I have forgotten something important I had to do. A little soul searching later, and it's apparent I am just feeling that a cigarette right now be really nice. It completely sneaks up on me, but the first few months this happened dozens of times a day, the first few days even more. If your autopilot makes the wrong choice just once, you're back to square zero.
Most of our life, we're in the passenger seat.
For example, the choice to open that one app leads to 30 minutes of scrolling leads to poor night's sleep leads leads to being on a later sleep schedule that week leads to not cognitively showing up to an important meeting that Saturday and missing an opportunity.
What we perceive of as 'big decisions' exist only within the conditions visible to our consciousness. Behind the scenes though those conditions are continuously shaped by small decisions amplified by the lever of the subconscious and our environment.
In other words, we're good at assessing the gravity of immediate conditions available to us, but we're bad at assessing internal and external processes and their effects. One reason why "know thyself" is such important advice.
Thus we'd be wise to make shaping conditions part of what we consider a 'big decision', perhaps even the big decision. This is another way of saying "we make our own luck".
If we’re talking about the small, unimportant decisions then sure, I agree. But I don’t think the bigger decisions happen on autopilot — precisely because it would be very dangerous.