Fiat saw its shares tumble 12 percent in Wednesday's trading, falling from 8.67 euros ($12.06 at today's rates) to 7.44 euros ($10.35) as of this writing, with blame partly going to the Italian half of the FCA marriage, which recorded a pretty significant drop in profits during the first quarter of this year.
The plan, which will cost around $77 billion over the next several years, is facing criticism from investors thanks in part to a 1.4-percent drop in Fiat's first-quarter profits, to 622 million euros ($862 million). That figure is also short of Bloomberg analysts' projections, which predicted $1.18 billion in profits before taxes, interest and one-time items.
"If you start your 2014-2018 plan with an extremely weak quarter, nobody will give you the credit that you will achieve your targets," Jens Schattner, a Frankfurt-based automotive analyst told Bloomberg. "If it was so easy just to launch new products to be successful in this industry, why wouldn't everybody do exactly the same."
Marchionne's goal of dramatically increasing sales before 2018 is a particularly big point of contention.
Some of the concerns are even simpler, though.
"These brands need a huge amount of work to get where they need to be. The world changes very slowly and you have brands at the bottom of the pile in many regions. It's not going to happen overnight," said Harald Hendrikse, a London-based analyst for Nomura Holdings.
Alfa Romeo and Maserati are perhaps the biggest points of concern, each brand facing its fair share of struggles over the years. Marchionne's goal of dramatically increasing sales (over five-fold for Alfa and nearly as much for Maserati) before 2018 is a particularly big point of contention.
"The aspiration is big but the questions are bigger," said Erik Gordon, a business professor at the University of Michigan. "Can Fiat do enough to turn Alfa into a big, profitable brand? Are there enough Maserati buyers to make Fiat a global player?"
While we like what we saw earlier this week in Auburn Hills, it seems fairly clear that there will be a number of bumps in the road along the way. Whether the analysts' concerns end up being correct, though, remains to be seen.