---
title: "[ Day 10 – Investment Diary ] + #MyInvestmentDiary"
type: "Topics"
locale: "en"
url: "https://longbridge.com/en/topics/100000000535314.md"
description: "Microsoft's biggest investment mistake was not in choosing the wrong company, but in failing to manage its position size and timing. After seeing the AI concept continue to gain momentum, it was driven by emotion to increase its position, ignoring the fact that valuations had already entered a high range."
datetime: "2026-03-18T15:44:45.000Z"
locales:
  - [en](https://longbridge.com/en/topics/100000000535314.md)
  - [zh-CN](https://longbridge.com/zh-CN/topics/100000000535314.md)
  - [zh-HK](https://longbridge.com/zh-HK/topics/100000000535314.md)
author: "[jssyczc](https://longbridge.com/en/profiles/25386465.md)"
generator: "portal-rs"
---

# [ Day 10 – Investment Diary ] + #MyInvestmentDiary

The biggest mistake in investing in Microsoft was not choosing the wrong company, but rather a failure in position management and timing judgment. After seeing the AI concept continue to gain momentum, driven by emotion, I increased my position, ignoring that the valuation had already entered a high range.

### Related Stocks

- [MSFT.US](https://longbridge.com/en/quote/MSFT.US.md)
- [MSFL.US](https://longbridge.com/en/quote/MSFL.US.md)
- [MSFO.US](https://longbridge.com/en/quote/MSFO.US.md)
- [MSFD.US](https://longbridge.com/en/quote/MSFD.US.md)
- [MSFU.US](https://longbridge.com/en/quote/MSFU.US.md)
- [MSFX.US](https://longbridge.com/en/quote/MSFX.US.md)
- [MSFY.US](https://longbridge.com/en/quote/MSFY.US.md)

---
> **Disclaimer: This article is for reference only and does not constitute any investment advice.**