Is it hard to build, market and maintain a web app that makes at least $1,000 a month?
The hard part is not getting to $1000 a month. It is staying there. Actually "staying there" is much harder than either "going beyond" or "falling back to $0" because Web/digital products (unlike say a baker's shop) are fundamentally not stable cash flow generators. They are unstable in either good or bad ways. The only thing worse than having a $1000/mo idea fall back to earth by itself is to watch someone else with more drive taking a clone to $10,000/mo and killing you in the process, because YOU didn't have the drive to run with it. This is a fundamental weakness of lifestyle business ideas. Good ideas have a tendency to quickly break the 4-hour-work-week effort ceiling. Bad ideas fall back to earth.
$1000 per month in a 100x$10 or 50x$20 configuration sounds simple. It is not. Development work for an average app, given the idea, is not particularly hard engineering, so if all you needed were the engineering chops for it, you should see one out of two engineers quitting their day jobs to do this. Why don't we see that?
It's because the hard part is not the engineering.
execution and growth?
To everything -- churn, churn, churn
There is a season -- churn, churn, churn
And a time to every product under heaven...
"A time to be born,
a time to die
A time to plant,
a time to reap
A time to kill,
a time to heal
A time to laugh,
a time to weep"
... and perhaps that's when you're $1,000 a month little business crashes back to $0