Yes. You are right. But the main thing is oil filter. Liqui Moly engine oil may last 8-10, may be even 13-15K Kms, but poor oil filter may not.
If engine oil + filter, both easily last 10K Kms, then for sure, you may go for Liqui Moly, however, if oil filter's life is just 5000-6000 Kms (as is usually the case here for locally assembled cars), then I think it is better to go for value for money brands and change oil + filter both after every 5K Kms.
Cost to benefit ratio may be overall same for both. However, if you are pouring Liqui Moly and changing it after every 5K Kms due to oil filter, then I believe it will be a waste of money in this case.
That's my personal opinion, others can disagree.