Google does want to follow the worthy and successfully established industry norm especially by two tech giants Apple and Samsung. Yes both develop handsets with their home-grown chipsets and has performed excellent in Benchmark results. For this reason, it is working to offer home-grown chipset to the Android devices of future. This is very similar to what Samsung does with its own line of Exynoschip set.
This is to bring more consistency in its hardware esp. when it comes to the high- segment. As there are bombardment of high performing high-cost a bit in-compatible chipset, thus is direly needed to develop more home-based highly compatible chipset that not only cut the cost but bring the true processing experience.
Custom processors will also reduce OS fragmentation in the short run and long run. To be more precise, we only need to look at Marshmallow 0.3 percent install base after a month to know that this is very much needed.
With devices related to more virtual reality centered future, this could be more difficult for a firm to get up to the mark anytime near short run, so Google has to make a decision quickly whether they want to commence with this idea or not, otherwise, they will be left far behind in this race of technology.