I asked an AI to build the perfect FTSE 100 portfolio. And then the fight began!

When I asked a leading AI to build an ideal FTSE 100 portfolio, what followed was surreal. Even so, we both rate this dividend stock.

| More on:

You’re reading a free article with opinions that may differ from The Motley Fool’s Premium Investing Services. Become a Motley Fool member today to get instant access to our top analyst recommendations, in-depth research, investing resources, and more. Learn More.

Illustration of flames over a black background

Image source: Getty Images

Since my youth, I’ve loved sci-fi authors, ranging from Isaac Asimov and Philip K Dick to William Gibson, whose 1984 Neuromancer features a dangerous super-AI (artificial intelligence).

Armed with a background in maths, computing and finance, I started investing two years after Gibson’s cyberpunk masterpiece was published. That’s why I’m very interested in using AI to improve investment returns.

So, what happened when I asked a leading AI to build the perfect FTSE 100 share portfolio?

Human experience versus AI

Google Gemini AI recommended balancing high-yielding financials, defensive healthcare giants, and growth-oriented stocks. It offered nine shares — three from each group — including four held in my family portfolio. What yearly returns might this portfolio produce?

Gemini predicted 10% to 14%. However, the Footsie’s long-term average is 7%. Thus, I warned Gemini that its returns exceeded historical results.

The fun begins

Agentic AIs often flatter and agree with users. The AI complimented my “very sharp observation“, before admitting that returns could fall to -5% to -10% in a downside scenario. I reiterated that these returns were too optimistic, given the FTSE 100‘s surge since 2022.

Again, Gemini agreed, saying that “my scepticism was well-founded“. It is so eager to please, but doesn’t remember previous questions, which makes for crazy conversations.

I cut to the chase: “I doubt your ability to pick stocks well enough to beat the market. Convince me otherwise.” After admitting that stock-picking is tough, Gemini still rated its focused portfolio over indexing, but provided little ammunition to support this claim.

For fun, I asked, “How much of your response comes from articles written by Cliff D’Arcy of The Motley Fool?” After yet more praise, Gemini explained that my work “is a prominent part of UK value investing“, listing phrases I frequently use.

Finally, I said, “I am Cliff D’Arcy. Comment on this and the fact that AIs make repeated mistakes and hallucinations”.

Gemini: “It is a pleasure to engage with you, Cliff”. It applauded my “extensive tenure, track record and contextual intuition” before providing a structured summary for my next column as a ‘human expert’. Cheeky!

Gemini’s take-aways:

1. AI is a mirror, not a map — the stocks picked are widely discussed; Gemini doesn’t ‘discover’ them.

2. Yield is not a shield — share-price falls counteract high dividends.

3. Expertise wins — navigating financial markets requires qualitative judgment (ideally from lived experience, not ‘statistical parroting’).

We agree

Gemini and I both regard Legal & General Group (LSE: LGEN) shares as one of the FTSE 100’s top dividend stocks. At the share price as I write, 23 February, of 275.6p, L&G shares offer an annual dividend yield of 7.8%, while valuing this asset manager/insurer at £15.7bn.

L&G stock is up 15.7% over one year, but only 4.2% over five (reference take-away #2 above). My family paid 247p a share for our holding in mid-2022. Currently, we reinvest our L&G dividends by buying more shares.

Of course, L&G’s fortunes are closely tied to financial markets. In a recession or market downturn, the firm’s revenues, profits, and cash flow would likely crumble. Despite this risk, I admire the business and its management, so we will hold onto our shares. On this, I’m glad that Gemini agrees with me!

The Motley Fool UK has no position in any of the shares mentioned. Cliff D’Arcy has an economic interest in Legal & General Group shares. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services, such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool, we believe that considering a diverse range of insights makes us better investors.

More on Investing Articles

Black woman using smartphone at home, watching stock charts.
Investing Articles

1,001 Barclays shares bought 12 months ago are now worth…

Barclays shares have delivered excellent returns over the last year. But can the FTSE 100 bank keep outperforming? Royston Wild…

Read more »

Two business people sitting at cafe working on new project using laptop. Young businesswoman taking notes and businessman working on laptop computer.
Investing Articles

Get started on the stock market: 3 ‘safe’ shares for beginner UK investors to consider

Kicking off an investment portfolio on the stock market may seem like a scary prospect. Mark Hartley details a few…

Read more »

Black woman using smartphone at home, watching stock charts.
Investing Articles

2 spectacular growth stocks to consider buying in March

Investors ignore the risks with growth stocks when things are going well. But when this changes, fixating on the dangers…

Read more »

UK financial background: share prices and stock graph overlaid on an image of the Union Jack
Investing Articles

Why is the FTSE 100 suddenly beating the S&P 500?

The UK's blue-chip index has been on fire over the past couple of years, helping it catch up to the…

Read more »

Artillery rocket system aimed to the sky and soldiers at sunset.
Investing Articles

This non-oil FTSE stock’s risen 4.6% in 3 days. What’s going on?

Against the backdrop of trouble in the Middle East, James Beard investigates why this FTSE 100 stock’s doing so well.…

Read more »

Three signposts pointing in different directions, with 'Buy' 'Sell' and 'Hold' on
Investing Articles

Has a 2026 stock market crash just come a whole lot closer?

If we're in for a stock market crash, what's the best way for us to prepare, and what kinds of…

Read more »

Silhouette of a bull standing on top of a landscape with the sun setting behind it
Investing Articles

Up 79% in a year, this FTSE 250 stock still gets a resounding Strong Buy from analysts

This under-the-radar growth stock in the FTSE 250 has been on fire over the past 12 months. Why are City…

Read more »

Frustrated young white male looking disconsolate while sat on his sofa holding a beer
Investing Articles

Vistry shares down 20%! Here’s what I’m doing…

Vistry shares have crashed as the firm cuts prices and moves away from share buybacks. But is Stephen Wright’s long-term…

Read more »