Despite attempting 26 shots on goal, Guardiola insisted his team did not create much to deserve the maximum points against Slaven Bilic’s men.
The Citizens were hoping to make a quick response after a toothless display in a dull 0-0 against local rivals Manchester United over the weekend.
Ilkay Gundogan's sumptuous strike gave Guardiola’s men the lead 30 minutes into the game, but the Baggies pulled parity on the cusp of halftime when Nigeria international Semi Ajayi's shot took a ricochet off Ruben Dias.
This result ended a run of eight straight Premier League home wins against promoted sides for the Manchester-based team, since a goalless draw against Huddersfield in May 2018.
Speaking to the media after the game, the Spanish coach was disappointed his team could not win but admits he does not know why the big teams keep dropping points so far this season.
“We could not win. We had the chance to win in the end. We were better than them but we could not not win,” Guardiola said with a grimace.
"They had physicality, we know that they can do well, we know that they are good. We know it. But we could not win.
"I don't know why [big teams have dropped points]. I haven't analysed the table but games like this, we have to win.
"The league is difficult. They are physical and strong and very good."
