Prepaid vouchers for local experiences are cool again, and Groupon (NASDAQ:GRPN) shareholders are riding high. The leading provider of flash sales has seen its stock move higher in back-to-back years, and the shares are inching slightly higher in 2018.

Groupon will get its first big test of the year when it reports financial results ahead of Wednesday's market open. Momentum remains bullish for this surprising turnaround story, but the comeback is not a slam dunk. Let's go over a few of the things that can work against Groupon's favor in Wednesday morning's report. 

A light green tile wall that reads GROUPON at the company's headquarters.

Image source: Groupon.

1. Revenue can't keep sliding

Groupon's stock may be rising, but revenue is going the other way. The online discounter has seen its revenue post year-over-year declines for three consecutive quarters. Analysts are holding out for more of the same on Wednesday morning, targeting a 9% drop to $852.8 million on the top line. 

There's a good reason for the cascading revenue. Groupon has retreated out of unprofitable international markets, sold off its Ticketfly ticketing business, and shifted away from lower-margin Groupon Goods offerings. Profitability has gone through the roof, so Groupon is making more out of less. However, the trend of negative revenue growth won't be a positive for too much longer. 

2. Profitability can fall short

Seasonality is a big deal for Groupon. It expects to generate more than 30% of its revenue and the lion's share of profitability in the holiday-spiked fourth quarter. Wall Street sees Groupon earning a record $0.09 per share in adjusted earnings for the quarter. 

Groupon has only met analyst profit targets in each of the past two quarters. The economy is holding up, and most e-commerce companies already came through with encouraging fourth quarters. However, there are so many moving parts at Groupon that even with it jacking up its gross profit guidance three months ago, we can't call its lofty earnings target an easy task. 

3. There are many unknowns

Groupon's chief products officer left the company last month, and it remains to be seen if it misses a beat in the transition. Can the initially well-received Groupon+ initiative offer sustainable improvement? Will growing its base of active customers -- clocking in at an impressive 32.5 million in North America -- be more challenging as it focuses on cost efficiencies?

Groupon has a lot of things going right these days, but there are enough uncertainties as the turnaround process plays out to make any financial update a potential pressure point. It's time to see if Groupon can deliver a record performance on Wednesday. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.