To some degree, this is the bargain that every spokesman strikes with their employer. Your own viewpoints are no longer relevant, and you are the standard-bearer of the company line. I know plenty of people who sympathize with Spicer, who resigned Friday after the hiring of new White House communications director Anthony Scaramucci, for having an impossible job.
But Spicer was asked to take the company line much further than the average spokesman — further than basically anyone I've ever seen in politics. And the results were often cringeworthy. From those earliest days, the question was often how long he could possibly last in the job, trudging out there day after day to defend a president who seemed addicted to false claims and controversy. Those false claims became Spicer's own. He became a literal laughingstock on “Saturday Night Live.”
Spicer accepted this as his fate and, for six months, was a good soldier — a good soldier peddling bad information.
Yes, spokesmen have to go out and say what their bosses tell them to, but they also need to retain their credibility. Reporters know they are being spun when they talk to a spokesman, but that person will generally work hard to make sure whatever they are saying is at least plausible and logical. Spicer never did that, perhaps because he simply couldn't. What he was being asked to sell — or chose to sell — was often irreconcilable with the facts, and thus he forfeited his credibility almost immediately.
Spicer was doing a job, but it's a job he signed up for and continued doing of his own volition, even as it became clear he would be asked to do what he did on Day One over and over and over again. On Friday, he was given a good excuse to bring it to an end, and he mercifully took it.