Almost two years into the worst slump of their lives, the song remains the same for oil and gas executives reporting (a lack of) earnings.

Business is so bad that it can’t help but improve, many of them say, in the indeterminate but not-too-distant future.

And, having said that, they outline investment plans designed to maintain their company’s contributions to the current glut. The market can balance at someone else’s expense. Investors lap this up and send more capital their way. Then everyone acts surprised when the glut sticks around.

This collectively self-defeating pattern now extends to the refining sector, busily converting the crude glut into a similar excess of finished fuels. Overcapacity has reared its head in the midstream space as well, though the pipeline builders have better lines of sight into recouping their investments eventually.

This dismal environment is proving especially draining for the integrated giants involved in refining as well as oil and gas extraction. We covered BP’s (NYSE: BP) uninspiring results last week. And yet those proved less disappointing relative to expectations than Friday’s reports by ExxonMobil (NYSE: XOM) and Chevron (NYSE: CVX).

ExxonMobil missed the consensus earnings estimate by a whopping 35% in reporting its lowest profit since 1999. Chevron hit the mark for operating earnings, excluding $2.8 billion in noncash writedowns on production assets no longer expected to cover costs.

Both supermajors continued borrowing heavily to afford generous  dividends and costly capital spending plans; in Chevron’s case its cash from operations so far this year wasn’t even quite enough to cover just the dividend.

Source: Chevron’s Q2 earnings presentation

Counting dividends, Chevron has outspent its cash flow by $17 billion over the last year, a deficit so wide it is unlikely to be entirely erased by spending cuts planned this year and next, as the company hopes.

The larger pure-play upstream producers are in the same leaky boat, though they’re overspending strictly to drill, rather than to yield. Many are plugging the gap with asset sales, and of course the buyers of those assets have their own investment plans.

So, for example, Devon Energy (NYSE: DVN) unveiled $1 billion in upstream asset sales in June (as part of a plan to realize $2-3 billion from asset disposals this year. Of that total, $200 million has been earmarked for a capital spending boost on the company’s core acreage.

One of the buyers was Pioneer Natural Resources (NYSE: PXD), which added acreage around its own core and plans to add 5 drilling rigs next month to the 12 it’s currently running in order to develop that resource. Pioneer sold stock to finance the acquisition. The company had generated $521 million in operating cash flow during the first six months of 2016, while investing $2.6 billion.

Big-picture forecasters continue to expect a diminution of the current glut next year as growing global demand catches up with increasingly constrained supply. But weekly inventory data continues to paint a much more bearish near-term picture.

So while Anadarko’s (NYSE: APC) CEO predicted last week that crude could rise to $60 a barrel by the end of the year, futures have moved south of $40/bbl today as traders focus on a persistent glut that still seems to be increasing.

Of course, if oil prices stay this low for long enough, the natural decline in output from legacy wells will overwhelm new output in shale basins and elsewhere. But it’s fair to ask, as most energy investors seem not to have done so far, whether the producers who overspent when crude was at $100/bbl in 2014 and at $30/bbl in 2016 will finally generate free cash flow at $60/bbl down the road.

Among those asking is the CEO of Schlumberger (NYSE: SLB), the leading global oil services provider. Here’s what he said on his second-quarter earnings call, after predicting a gradual increase in drilling worldwide:

“The sustainability of this activity recovery will be defined by the financial viability of the entire oil industry value chain, which will vary significantly from country to country. And in places where the total value chain remains in a chronic financial shortfall, the increase in activity will not be sustainable.

A key question in this respect is the sustainability of a North American land recovery where the cumulative industry earnings and free cash flow was negative over the last cycle. And given the resulting financial state of the value chain in this commoditized market, a large wave of cost inflation from every part of the supplier industry is now building, which the E&P companies will have to absorb in parallel with implementing their activity growth plans.”

It’s true that the oil business right now is so tough that it’s bound to get better. The question is whether that improvement will lift share prices that have already rallied hard in anticipation of that change and mop up the persistent cash flow drain. As our defensive investing posture suggests, we have more than our fair share of doubts.