Why did Drake and Future come together for WATTBA?

Now that Drake and Future's collaborative album What A Time To Be Alive is out, the first question worth asking is why did these two come together at all? Drake and Future are easily rap's biggest names at the moment and while they technically have a history together, the music they've made hasn't necessarily left more collabs to be desired. When Drake jumped on "Tony Montana," that was one of the first times Drake chose to hop on a song by a lesser known artist nationally whose song was very successful regionally as a way to boost his own image. That song was even that big of a hit, and it's still the most successful song they've had together. Part of that is the technicality that "Bitches Love Me" was a Lil Wayne song, but the other tries – "Never Satisfied", "Shit (Remix)", "We In This Bitch 1.5" – all came and went.
Drake was the only feature on Future's DS2 and that's likely how the idea for this album came about. Future had been on a unbelievable run in 2015, so of course Drake, who continues to delay his own album Views From The 6, decides to hop on that wave. And for Future, the quick success at radio for "Where Ya At" because of the sheer presence of Drake and the potential to expand his fanbase are the likely catalysts for a project like this. So in that sense, WATTBA had a purpose – to keep both their name's hot – even if only Drake needed that to happen. And as a result the album feels like a very clock-in-clock-out job.
It's evident that Future and Metro had most of these songs in the stash before Drake came into town. Four of the nine joint songs showcase Future on both the first verse and the entire hook while Drake only contributes one verse at the end of each. The songs that sound more like equal parts Drake and Future almost feel out of place on the album. "Change Locations," produced by Drake co-hort Noel, is downtempo and elicits 40's old low pass filter. They trade places on the hook, but it becomes a Drake song on an album that doesn't need one.
Were this a solo Future project, it would continue his solid streak of solo tapes but would probably fit in somewhere between Monster and Beast Mode on the tail end of the rankings. "Diamonds Dancing" is the obvious highlight. I don't know how many other songs could make you want to cry and throw money in a strip club at the same time. If anything, Drake's involvement was a detriment to both the album and his own star power. Drake can have a positive impact on other artists' songs, clearly, but he can also really drop the ball and it's fair to say he does not fit on songs like these and we probably shouldn't let him get away with him singing hooks like "Live from the Gutter" and "I'm the Plug."