During steam days a "factor of adhesion" of 0.25, or 25%, was in common use for calculating maximum tractive effort. That was, bluntly, the highest coefficient of friction which a dry wheel on dry smooth rail could sustain. If, say, 40,000 pounds of weight was on a single powered axle then attempting to exert more than 10,000 pounds of force ahead (from engine power) or back (from braking) on that axle would cause the wheels to slip. Wheel slippage Is Not Good; it damages both wheel and rail.
An engine with insufficient power to exert 25% traction at the rails was regarded as underpowered. On The Other Hand, an engine with too MUCH power for its weight was regarded as "slippery"...it would regularly "slip" on the rails and as such could not be operated at its full potential without causing damage. So, for
Pere Marquette 1225 (an engine I have some passing familiarity with) the "adhesive weight" (or weight on drivers) was 277,600 pounds out of its 442,500 pound locomotive weight...in other words, 164,900 pounds of the locomotive weight rested on the unpowered wheels (pilot axle and trailing truck). The rated tractive effort was 69,368 pounds (force), or almost exactly 25% of the weight on drivers.
The same basic principles apply to Diesels, at least as far as slippage is concerned. So a Centipede with 409,000 pounds on drivers would be expected to top out at approximately 102,000 pounds tractive effort. The difference, as Siegmund pointed out above, is in the power train. A Diesel can only run high amps through its traction motors (for starting and low-speed pull) for a very brief time without risking overheating the motor and generator windings. A steamer, OTOH, can sit stopped with throttle wide open (say, on a heavy grade with a long train) essentially all day long with no ill effects. But on that OTHER other hand, a Diesel with a given horsepower rating can exert more pull/tractive effort at its wheels for its weight and power than a steamer can.
Once the train starts moving, as also was pointed out above, Diesels are power-limited by the rating of their prime mover. A steamer's power limitation comes from its boiler's ability to generate steam, which essentially translates into how fast the fireman can shovel coal into the firebox...and for a stoker-fired Super Power locomotive like PM 1225 that really isn't much of a limitation....
Edit To Add: That 25% coefficient of friction, as stated, was for dry wheels on smooth dry rail. Throw some water or leaves/debris into the mix and that COF goes down dramatically...and wheels slip. On the other hand (again), slightly roughened rails can raise that COF slightly. That's why locomotives, both steam and Diesel, are equipped with sanders. If the loco begins to slip, spraying a little sand between the (driven) wheels and the rail can raise the COF back up to a number at where a slipping locomotive can begin to move its train.