Don’t put all your egg in the same basket. We have all eared this. A lot of scams are using this to squeeze you like a lemon until you don’t have any more money to spend. Then they go to the next lemon and squeeze again.
The fact is you can’t use this with a business. If you start a business, you aren’t going to be more successful starting another one or even two other. The more you open the more chances you have to fail.
You can start a second business if you want, but you should do so only when your first one is earning you enough money to invest in the next. You should always ask yourself if you can take care of another business.
On a day to day basis, if you focus on one business and make it work, you’ll get more success then if you try to build many at the same time. You’ll only separate your energy into each of them. Never give enough to each of them to make them grow. So you’ll end up with many useless businesses instead of a profitable one.