The Dow Jones Industrials (DJINDICES:^DJI) weren't able to press into record territory on Friday morning, falling 30 points into the red as of 11:30 a.m. EDT after getting to within about 20 points of a new all-time closing high yesterday. Economic data pointed to sluggish consumer spending, but the biggest decliner in the Dow was Caterpillar (NYSE:CAT). Nevertheless, even though Caterpillar's big news today involved the departure of a key executive, smart investors need to look beyond those headlines to see the real reason why shareholders aren't entirely comfortable with the heavy-equipment manufacturing business right now, especially in light of trends at peers Joy Global (NYSE:JOY) and Deere (NYSE:DE).

Source: Caterpillar.

Most commentators blamed Caterpillar's 1.7% drop this morning on the departure of Chief Information Officer Randy Krotowski, who announced his resignation effective Sunday to pursue unspecified further endeavors. Krotowski had only been at the company since early 2012, but his three decades of experience at one of the energy giants in the Dow Jones Industrials gave him the knowledge to pursue closer relationships with Caterpillar's dealers and customers and put in motion a long-term strategic plan to get information technology solutions to help customers use equipment better and for dealers to manage their businesses more effectively.

Yet Caterpillar also faces ongoing challenges in the broader fundamentals of its business. Last week, the Dow component reported overall machine sales fell 13% in the three-month period ending in April. Most of that weakness came from its mining-equipment segment, which is suffering from big declines in commodity prices that have forced mining-company customers to cut back on capital expenditures for equipment. Joy Global is even more exposed to those factors due to its greater focus on the mining industry. Caterpillar does have pockets of strength, as its construction segment has seen sales finally start to rebound as the strong North American market finally asserts its importance in the company's overall operations.

Source: Deere.

Meanwhile, some argue that Caterpillar isn't as strong a company as Deere, which has focused on the agricultural segment and has enjoyed great success in serving that booming industry. Yet both companies face the cyclical nature of their respective businesses, and it's inevitable that Caterpillar, Deere, and Joy Global will all have to endure down periods. What's unclear is how long sluggish periods will last, and globally, Caterpillar has to deal with different economic conditions that have a big impact on its overall business.

Executive departures are never good news for a company. But the big question for Caterpillar and for the Dow Jones Industrials more broadly is whether a long-awaited upturn in the usual cyclical businesses in the U.S. economy will finally appear and spread worldwide. Until that happens, Caterpillar's prospects will remain in question.

Dan Caplinger has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.