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Understanding matters when it comes to career,you have to know and understand the type of person you are,if you are a one career person or you can actually go through more than one career and succeed in them,get to know yourself first.I have seen some people go through multiple careers and they do well while some didn't do well,you should know what works for you better and what doesn't.
Some people are destined with two to three things that they can do well while some with just one,but most times those people that have two to three careers function well In one or two out of the rest.
Focusing on one career makes it better for you not to be distracted,you put all your energy in that career,so that it will flourish.
For someone like me I can go through just one thing at a time even though I have two to three things to do but just one at a time,if I focus all my attention on one so that it will blossom well,then I can move on to the next one, while that other one is still succeeding.

I'm a multiple career person,I know I can't go through just one career in the course of my life but I can take it one step at a time so that I won't fail In them,I will have to start one first and succeed in it before I move to the second one, multiple career makes you have different streams of income but it must be a successful one.
In this modern age there are lots of career paths that can be followed,there are alot of online learning and certification,it doesn't have to be physical,you learn two or more skills online and grow in them,if you take them serious then success is a sure thing.
This is where the oil money is nowadays, following the technology trend and learning is part of growth,it doesn't have to be so hard, just find what you want to do or love to do and grow in it.

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Advantages of a multiple career choice:

1. Multiple streams of income - multiple career choice tends to give multiple streams of income,it helps in payment of bills and having extra or enough.
2. Flexibility -You will have something to fall back on when one fails,you won't need to start all over again or be in deep sorrow, your financial capacity won't suffer.
3. Diverse skills - it helps to experience different skills across different career path,it gives the knowledge other people don't have and helps you get better.

Disadvantages

1. Slow growth- it tends to be slow in growth because all your attention is diverted to different career,you are not focused solely on one,instead of growing one, everything tends to be slow,it can also lead to not achieving anything like the saying goes "jack of all trades master of none",you might loose everything when trying to go through more than one career path.

Advantages of one career choice:

1. Fast growth- One career choice tends to grow faster,it makes it easier to focus more on one and use all your energy in making it grow into a large business.

2. Ability to succeed - it gives you the ability to succeed more because when you focus only on one,you will do all your research and work only on how to make that particular business succeed.

3. Job stability - when you specialize in one area,it can offer you a job stability which you can depend on.

4. Deep expertise - It helps you to be more skilled when you focus on one career because all you have been learning is just about that one career,it gives you an edge over others.

Disadvantages

1. Limited flexibility - There will be nothing to fall back on if the company or career faces on challenge or another,it will be hard to start a new business or all over again.
   2.Just one stream of income- You are limited to just one stream of income,either it's enough or not,it's just source of income everytime,it might not pay all your bills not to talk of having extra.

Conclusion: At the end of the day each person should know the best choice for them and how they can handle it.