It is interesting to hear/see that when older startup companies (let's 5 or or more years) always start with a background of the market and the company. Back in 2005, this happened, we did that, then this, then we got acquired, then this.

The audience is probably not really interested, they want to find out about today's products or investment opportunity.

So why this habit? It is hard to change your company pitch once you have gotten used to it. Back in 2006, that intro about what happened in 2005 probably was really important to the story. In 2016, it no longer is.

Contradicting myself, this is probably not true in all cases. The company Slack, for example, was born out of a side project for team communication of a failing game development company. That's an interesting detail to bring forward. Keep it short though.