A good historian does not simply replicate information from sources, but provides some evaluation of them too, so that the reader is able to judge how much reliance to place upon them. This is one reason why modern historians are much more reliable than ancient historians, because they are far more likely to do this.
You're never going to be able to compile a definitive encyclopaedia of all history. This is the sort of thing people tried to do in the late seventeenth century, and it never worked, because there is simply far too much information. No one person can ever have enough knowledge to compile it. I recently wrote/compiled a history of the church which tried to take in its complete history over the whole world. It only skimmed the surface of practically everything and I could have made it twice as long without any difficulty. It took three years to do, and that was only a small snippet of history. I also just finished writing an encyclopaedia of Christian writers from the second to the thirteenth century. That took six years, and, again, is only a small snippet of history.
You're never going to be able to compile a definitive encyclopaedia of all history. This is the sort of thing people tried to do in the late seventeenth century, and it never worked, because there is simply far too much information. No one person can ever have enough knowledge to compile it. I recently wrote/compiled a history of the church which tried to take in its complete history over the whole world. It only skimmed the surface of practically everything and I could have made it twice as long without any difficulty. It took three years to do, and that was only a small snippet of history. I also just finished writing an encyclopaedia of Christian writers from the second to the thirteenth century. That took six years, and, again, is only a small snippet of history.