“I didn’t retire. I just needed to heal physically, mentally. I had no plans. I just didn’t know when I would come back. I didn’t know how I would come back,” said the 40-year-old on Saturday.
The American star will return to singles action at Wimbledon next week for the first time since her tearful exit from the All England Club in the first round in 2021.
The seven-time Wimbledon champion is chasing a record-equalling 24th Grand Slam title.
However, her lengthy absence from the sport has seen her world ranking plummet to 1,204th.
She needed a wildcard to play Wimbledon this year as she seeks a first major since capturing the Australian Open while pregnant in 2017.
Her last appearance at the All England Club ended after just six games when she was forced to quit her Centre Court opener against Aliaksandra Sasnovich.
Having made her debut in 1998, Williams said that she didn’t want that heartbreaking exit to be her last memory of Wimbledon.
“It was a lot of motivation, to be honest. It was always something since the match ended that was always on my mind.
“Wimbledon was tough last year. I felt like I was injured for most of the year. Then I ripped my hamstring.
‘Who knows where I’ll pop up’
“I still tried to make New York. I gave everything I could, just every day getting ready or trying to make it. But then it’s just like, I’m not going to make it. Hung up my racquets for a little bit until I could just heal.”
In a change to tradition, and with a nod to the gravity of Williams’s injury last year which was caused by her slipping and falling, organisers have allowed practice sessions on Centre Court.
The aim is to bed in the grass so that players can enjoy immediate grip on the world’s most famous patch of grass.
“On the one hand it’s amazing, but on the other hand it’s like, we have to preserve Centre Court,” said Williams.
“Obviously I was super happy to be out there and have that opportunity, and it was also good for me to get that out of my system because the last moment I had on Centre Court was probably not my best moment.”
Williams said she decided before the French Open to make her comeback at Wimbledon and to warm up for the big occasion, she played two matches in doubles with Tunisia’s Ons Jabeur in Eastbourne.
“Probably could have played singles there. I felt more prepared than I thought I would have a month or two months or three months ago,” she added.
Her rivals at Wimbledon, which gets underway on Monday, are delighted to see the American back on court.
“I saw her yesterday, I was pretty overwhelmed,” said world number one and recently-crowned French Open champion Iga Swiatek.
Coco Gauff described Williams as “always a contender to win, even if she hadn’t played for a year”.
“I remember watching that match a year ago where she had to finish short. I thought maybe that would have been the last time we saw her play at Wimbledon,” said the 18-year-old.
Williams, meanwhile, was not in the mood to discuss her long-term future in the sport and whether or not this is her last Wimbledon.
“I can only tell you that I’m here. Who knows where I’ll pop up next,” said the American who turns 41 in September.