Research, the act thereof, can prove perilous. When writing fantasy, one needs to be as rigorous with reality as possible so as to ground the fantastical elements; the best way to achieve verisimilitude is to make the mundane sound authentic. Which, inevitably, requires research.
What’s wrong with that? Where lies the danger? Here: research is fun. One thing links to another. There’s always room for more information, interesting anecdotes, potential spin-offs. Like novels, research is never finished, merely abandoned, and the mark of a good writer is knowing when to stop research and start writing.
An obvious example is historical fiction. Say you’re writing about the creation of a Byzantine boy-band. What kind of music was popular back in Anatolia? Were barbershop quartets in? What instruments were used? Did they dance as they sang? Where would they perform? Clearly some research is in order. But from there, you can begin to ask other questions: did they have indoor toilets? What sort of transportation did they use? Were they cuckoo’s for cocoa puffs? What about deodorant?!?!
But even the writing of a modern novel can be dangerous. Which government agency would be responsible for dealing with this problem? How is it organized? Would they send one agent or two? Would they carry guns, would their authority supersede that of local police?
Or you could begin asking questions like, how does flooding affect subway tunnels? Would the power short out, or would the who mass become dangerous to touch? Where would all the rats go? Would sewage backflow up into apartment buildings? Are their emergency drainage systems?
And on and on it goes. Whether researching animals for models of monster behavior, researching historical events or institutions, whether figuring out how utility or governmental authorities respond to crises or the religious beliefs of different groups, a writer can become lost in his research, and accumulate endless amounts of knowledge.
Which then run the risk of drowning the original story in too much information, of the writer losing the energy and desire to write the original tale, having become overwhelmed by the sheer volume of data now at his disposal.
So, research. Fun, perilous, necessary, addictive.