Joel Spolsky looks back at his time at Microsoft, during its glory days in the early 90s, when Bill Gates himself would read a spec and grill the designer:
He was flipping through my spec! (Calm down; what are you, a teenager?) And there were notes in all the margins! On every page! He had read the Whole Darn Thing!As the conversation went on, Bill’s questions got harder and more detailed. And they seemed a little bit random. But I didn’t care. By now I was used to thinking of Bill as my buddy — a nice guy who had read my spec. In my head, I was already thinking of how I would address his comments, pronto.
Finally, the killer question. “I don’t know, you guys,” Bill said. “Is anyone really looking into all the details of how to do this? Like, all those date and time functions. Excel has so many date and time functions. Is BASIC going to have the same functions? Will they all work the same way?”
This was exactly the question I had spent the previous day investigating. And as I had discovered, there was a discrepancy. In both Excel and BASIC, each date was assigned a numeric code. The code for any day in 1992 that I looked up was the same in both. But when I looked up a date around the turn of the last century, Excel and BASIC were one digit apart. Huh?
When I went to find someone who might be able to help, I was directed to Ed Fries, a longtime Excel programmer famous for inventing those screen savers with the swimming fish. I hadn’t had much contact with Ed, but I used to see him every Friday afternoon as he played miniature golf in the hallways outside my office.
“Check out February 28, 1900,” he told me.
Its number in the Excel code was 59.
“Now try March 1.”
Its number was 61.
“What happened to 60?” Ed asked.
“It’s February 29!” I said proudly. “1900 was a leap year!”
“Nope,” Ed said, and left me pondering the problem for a little while longer. I eventually figured out, with some more guidance from Ed, that a group of programmers at Lotus had skipped a day in 1900 because it created a mathematical shortcut for them, and they probably figured that nobody would care about a mistake buried in the software’s internal calendar more than 90 years in the past. The people who made Excel hadn’t cared at all and built the bug into the code that the spreadsheets ran on. But the people who had written the code for BASIC had apparently been offended by the shortcut, so they set the start of their internal calendar a day earlier. That way, it would accurately reflect the actual calendar, but the solution was also practical. Because BASIC started its count a day earlier, the number that BASIC assigned to March 1, 1900, was also 61, and from that point on its date and time functions were aligned with Excel’s.
So were the date and time functions compatible?
“Yes,” I told Bill. “The dates are exactly the same, except for January and February 1900.”
Silence. The F Counter and my boss exchanged astonished glances. How did I know that?
“OK. Well, good work,” said Bill. He took his marked-up copy of the spec…wait! I wanted that…and left.
“Four,” announced the F Counter, and someone said, “Wow, that’s the lowest I can remember. Bill is getting mellow in his old age.” He was, at the time, 36. Later, I had it all explained to me. “Bill doesn’t really want to review your spec,” a colleague told me. “He just wants to make sure you’ve got it under control. His standard MO is to ask harder and harder questions until you admit that you don’t know, and then he can yell at you for being unprepared. Nobody was really sure what happens if you answer the hardest question he can come up with, because it’s never happened before.”
What did I take from all this? Bill Gates was amazingly technical, and he knew more about the details of his company’s software than most of the people who worked on those details day in and day out. He understood Variants and COM objects and IDispatch and why Automation is different than vtables — and why this might lead to dual interfaces. He worried about date and time functions. He didn’t meddle in software if he trusted the people who were working on it, but you couldn’t bullshit him for a minute because he was a programmer. A real, actual programmer.
Watching nonprogrammers trying to run software companies is like watching someone who doesn’t know how to surf trying to surf. Even if he has great advisers standing on the shore telling him what to do, he still falls off the board again and again. The cult of the M.B.A. likes to believe that you can run organizations that do things that you don’t understand. But often, you can’t.