Answer :
One explanation I can think of is:
If you wanted to travel "around the world" you need to fly or take ships/boats at least between the continents, but realistically much more. This would be probably at least 5 000 assuming that you always catch the best deal.
Further, you might have to pay some Visas: for example The Visa for India costs around 100 Dollars. Let's say You'll spend another 1000 on visas and administrative fees
Further, you need to buy food during this time. with a budget of 10000 - 6000, you'd have only 4000 left, around 160 dolars a month - which would not be enough, since it takes experience to know where to buy cheap food in unfamiliar countries.
And in all of this - i didn't even count the cost of transport, which would easily amout to 10 000 in smaller regional planes and trains ( it's barely thinkable you'd catch a ride from Spain all the way to China...)
If you wanted to travel "around the world" you need to fly or take ships/boats at least between the continents, but realistically much more. This would be probably at least 5 000 assuming that you always catch the best deal.
Further, you might have to pay some Visas: for example The Visa for India costs around 100 Dollars. Let's say You'll spend another 1000 on visas and administrative fees
Further, you need to buy food during this time. with a budget of 10000 - 6000, you'd have only 4000 left, around 160 dolars a month - which would not be enough, since it takes experience to know where to buy cheap food in unfamiliar countries.
And in all of this - i didn't even count the cost of transport, which would easily amout to 10 000 in smaller regional planes and trains ( it's barely thinkable you'd catch a ride from Spain all the way to China...)