Good question Pete.
Some of my initial thoughts (in order of importance):
1) Research - do you know fundamentals of this company inside and out?
2) Patience - how many investors get rich quick?
3) Resilience - can you ignore the "sky is falling" clowns on this forum?
4) Insights - do you know the technical/analytical charts well?
5) Trust - do you trust the leaders and your own intuition?
6) Past performance and future potential - do you know what this company has done and where it could end up?
7) Appetite for risk/reward - do you understand the obvious upside and downside of this company?
The answers to each of these questions assists in our decision making (buy or sell).
I use a combination of the above to invest, and the most recent announcement has given me more confidence in the decision i made to initially invest in 9SP, and the decision i made to buy more today @ 2.7c.
If the last announcement combined with the recent surge in volume of trading doesn't give you any confidence, then perhaps the tech sector is not the right place for you.
Sentiment = mad to be selling.