What are the non-business reasons to not "start-up"?

I am very interested in having a better understanding of the reasons that someone should keep their project as a hobby rather than trying to make it a "start-up"

What would be the non-business reasons to keep the project in the garage in the garage?

Not because it "couldn't" but perhaps because it could but it shouldn't, or the personal costs would be too high.

Thanks!

Well it needs to be your obsession ... not something you tinker with.

There are a fair few reasons not to start, sometimes I advise people not to

1. You have clients hassling, suddenly you have 100s of bosses ... many can seem more like screaming children.
2. Family members are a hard balancing act. Ensure your better half (if you have one) is going to back you in your venture.
3. Not everything works really well or dies, they just sit in the middle being almost ... you can get stuck with obligations.
4. Other hobbys will take a back seat. If you like doing a range of other things, travelling, sports etc ... they are likely going to fade out for a few years at least.
5. You work your own hours ... all of them. You start feeling like if your relaxing on the couch then your wasting time.
6. Money will be tight for a while. You don't get to do all the normal things your used to.
7. You don't get to keep doing the thing you love (in my case programming) all the time. Suddenly you also get to do HR, Marketing, Sales, support, training of staff, writing plans, dealing with legal issues ... and a whole bunch of other stuff that you were only vaguely aware existed previously.

But the key ones are:

1. Your family
2. Your free time
3. Your real passion (building a business OR tinkering with your toy)

But like having kids, most days it is worth it :)

Reasons not to?

Confidence - you're simply not convinced it's that certain of success to quit the day job, so you launch it as a part time project. (Now there's much to be said for the mere fact it's a part time project means it's less likely to work, reinforcing your opinion. The lack of time, budget and commitment makes it less likely to be noticed)

Similar to the above...
Triviality - it's a nice idea, but it simply doesn't seem big enough.

Mindset - there's many talented coders out there who can produce a fine piece of shareware, or something on a part time basis, but are filled with terror at the thought of ditching the day job without the certainty in something else to go to. Or perhaps an irrational fear of sales and marketing etc. I think to get going in startups you have to have basically accepted that simply trading time for money is irrational. :)

Personal - for instance if you've just started a family and need some predictable level of income and free time, a startup is probably the wrong place to be. In this case you get to choose between divorce and keeping it a hobby.

I see two sides to this.

Would you enjoy doing it full time? Or is it better suited / more rewarding keeping it a hobby. If you start working on it full time, your hobby can turn into work. If you really love it, it could turn out to be a great proposition. To quote Confucius "Choose a job you love, and you will never have to work a day in your life".

The other one has to do with what you have to leave behind. Do you enjoy what you're doing right now full time, have opportunities to work on something you couldn't on your own, gain experience you couldn't on your own, or are you part of a great team? Do you want to leave that behind? What do you want to do? Do you want to grow professionally more? Would it be more useful to stay there longer?

But the most important by far is if it makes you happy.
If you're happy keeping it as a side project, it's fine. If you love your job that's fine too.

Really that's the driving factor. Follow your passion. Money is a motivator, but it's a poor one if it's not backed by passion.

There's no requirement that everybody has to start a company. Working for a company you like, doing things you enjoy are equally rewarding.

If you don't really like that job, or don't find it necessarily rewarding, ask yourself what's keeping you from jumping on the bandwagon.

"When you marry your mistress, you create a job vacancy." - Sir James Goldsmith

Translation : if you turn your hobby into a job, you will need another hobby.