Managing a roster is far from being easy, wherever you are in the league. You need to hire the best assets possible at the cheapest possible price and still stay under the salary cap constraints imposed by both the NHL and the NHLPA.
Bob McKenzie has a very interesting information about the ongoing state of affairs in the league as of tonight.
This may seem trivial, but there's a huge implication with this year's expansion draft. The more money teams have to spend (especially Vegas) the better player they can hire/keep. Moreover, the UFA season is fast approaching too and it will probably be a very wild market. All these added together makes for a very uncomfortable delay at this point.