Catman, I think you are not recognising the nature of diamond...

Catman, I think you are not recognising the nature of diamond exploration. Very few companies only have 1 target area as they understand the likely-hood of hitting a profit making mine. Lucapa have been exploring Lulo for 15 years? and have found a profitable alluvial source and many targets but yet to find a profitable diamond pipe.
If you are to be taken as a serious diamond company you need to be examining as many options as possible with your resources available. If you say just focus on one you may pick the wrong one!
You can argue they got it wrong with Mothae but they would have been remiss to not have assessed it.
Lucara had Mothae previous to Lucapa, based on your plan they should have just focussed on it, but they took on Karowe and now have a highly profitable mine.
A profitable mine may last as little as 4-5 years, so what then if you have nothing in the pipeline?