“Karko Bhaav Nashyati” is not easy to interpret and it applies sometimes only not every-time, also applies for every planet.
If someone is using only D-1 or Rashi chart then it does not apply as well. You’ve to use vargas to confirm it.
Jupiter is the karaka of 5th and 9th house both, also 2nd house and stability of 11th house of income.
Now, if we start taking “karko bhaav nashyati” then:
1. Jupiter in 2nd, 5th, 9th, 11th will lead to this “karko bhaav nashyati”.
2. Then Jupiter in 6th, 8th and 12th. People will say karaka in trik houses. So, again bad.
3. 3rd house is his “maran sthan”. Again bad.
We are left with 1st, 4th, 7th, and 10th house only. Where 7th Jupiter is bad for married life in some cases.
Are you getting my point?
I only want to say that “karako bhava nashyati” is not a general rule. And not applies every-time. If we take it as general rule nothing will be left for Jupiter in horoscope except 4 houses.
Similarly, it applies with other planets.
So, now how this applies:
1. Any planet in his karaka bhava will not destroy it, until that planet is in lagna of that particular divisional chart, whose karka is planet itself.
2. Means, Jupiter in 5th house of children will not destroy it, until Jupiter is in
Lagna of D-7 chart of children. 5th house is also our learning. So, Jupiter in Lagna of D-24 (chart of learning) will destroy learning but not children if it is not in lagna of D-7.
This is the major principle. Sometimes if karka is not in karka bhaav in D-1, but it is afflicted and found in lagna of the divisional chart where he is karka then also it destroys that thing. For example: Saturn afflicted in D-1 and is in lagna of D-10.
But, please please don’t take it dogmatically. If that karaka is very strong and aspected by benefics then negatives are less and if aspected by malefics and weak then situation can be worst.