"I didn't expect to play this well so quickly into my comeback", Williams said after the match.
Kerber has her heart set on winning a first Wimbledon title after booking a return to the final.
"[But] Every time I go out there, I want to I guess take a giant step forward, keep taking giant steps, but keep improving".
After hitting five aces with a serve that reached 119 miles per hour, delivering 16 winners to only seven unforced errors, and covering the court so well with speed and effort against Goerges, Williams will face another German, 11th-seeded Angelique Kerber, on Saturday.
The seven-time Wimbledon champion will face Angelique Kerber in a repeat of the 2016 final, which Williams won, after the German beat Jelena Ostapenko earlier. Sure, she was playing in her 11th Wimbledon semifinal and was 29-5 in Grand Slam semis before walking onto Centre Court to play world No. 13 Julia Goerges on Thursday.
The first two points played by Ostapenko - who won the French Open in 2017 and crashed out in the first round the following year - were emblematic of the match. Ostapenko: Winners (30), Unforced Errors (36); Kerber: Winners (10), Unforced Errors (7).
"These are the matches I was working for as a young kid", Kerber said, "and to stand here again in the final at Wimbledon is great".
"I lost count after, like, four surgeries", said Williams, who has been wearing compression leggings this fortnight as a precaution.
She completely controlled the game and crucially broke to 4-2 in the opening set.
A jubilant Williams was back giving the crowd a one-arm raised victory twirl after reaching a 10th Wimbledon final when her opponent swiped a lob behind the baseline.
"This is not inevitable for me". "I had a really tough delivery, and I had to have multiple surgeries and nearly didn't make it, to be honest".
'I remember when I couldn't even walk to my mailbox, so it's definitely not normal to be in a Wimbledon final'.
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Leading 4-2, Williams powered into a one-set lead, breaking Goerges to love to move ahead.
It was the first time at these championships that the American had faced a player ranked in the top 50 and she stepped up with a powerful display that also showed better movement around the court than in previous rounds.
There were moments when watching Goerges made it easy to wonder how it could be possible she never had been past a major's fourth round until now. I know it will be a full house there.
"I still have a match to win", she said. There was one brief blip to come: Williams got broken for the only time while serving for the match at 5-3. After a double-fault helped hand Williams a break point, Gorges failed to clear the net with a drop shot.