Slopes, peaks, and valleys

As John Ousterhout puts it, a little bit of slope makes up for a lot of y-intercept.

Two careers: one starts ahead, the other learns faster and passes it

Time	intercept	slope
0	4.25	1.46
6.5		10
10	6.33

Ramp hires for slope by name, and Jane Street calls a finance background optional. Traditional interviews miss slope, part of why I prefer work trials. It's contagious, too: teachers improve faster when their colleagues are better. That is the real case for talent density. A company's curve is the sum of its people's, so collective slope sets how fast it grows.

Zoom in, and each of those people is a line of skills, with similar skills sitting close together. Peaks are strengths and valleys are weaknesses. Many peaks, far apart, make a generalist; one or two make a specialist.

Ability

specialistgeneralistexceptional generalistfar apart: it barely fillsnearby peaks: the valley fills

Skills (similar skills sit close together)

A specialist, a generalist and an exceptional generalist, with two valleys filling in

Skills (similar skills sit close together)	specialist	generalist	exceptional generalist
0	-0.17	-0.03	0.19
0.1	-0.27	0.45	0.19
0.2	0.18	0.01	-0.14
0.3	-0.1	-0.23	-0.3
0.4	-0.26	0.01	-0.15
0.5	-0.46	-0.02	0.76
0.6	-0.07	-0.19	0.66
0.7	-0.1	0.03	-0.22
0.8	-0.47	0.23	-0.17
0.9	-0.21	-0.03	0.56
1	-0.13	0.16	-0.09

The valleys between nearby peaks are the easiest to fill. In my experience, high-slope people fill their valleys faster. Working with people who peak where you want to grow fills valleys and extends peaks.

The best leaders know each person's peaks, and the valleys they want to grow. They scope work to peaks, give bonus scope in valleys, and expose them to the right people. High-slope people take on more of that bonus, because they simply move faster.