Why it's not recommend to send too many mail at same time ?

Sending too many emails at the same time can have several drawbacks and may not be recommended for the following reasons:

1. Email Service Provider (ESP) Limitations: Email service providers often have limitations on the number of emails you can send per day or per hour. If you exceed these limits, your emails may not be delivered, or your account could be flagged for suspicious activity. It's important to check and comply with the sending limits set by your ESP.

2. Deliverability Issues: When you send a large volume of emails simultaneously, it can trigger spam filters and email providers may perceive it as suspicious or spam-like behavior. This can lead to your emails being filtered out or sent to recipients' spam folders, resulting in lower deliverability rates.

3. Server Overload: Sending a massive number of emails at once can put a significant load on your email server or the infrastructure provided by your ESP. This can lead to slower sending speeds, delays in email delivery, and potential system crashes.

4. Recipient Reactions: Bombarding recipients with a sudden influx of emails may result in negative reactions. They may mark your emails as spam, unsubscribe from your mailing list, or perceive your communication as intrusive. Building a positive relationship with recipients requires respecting their inbox and sending emails in a controlled and thoughtful manner.

5. Tracking and Analytics: Sending a high volume of emails simultaneously can make it challenging to track and analyze the effectiveness of your email campaigns. It becomes difficult to monitor open rates, click-through rates, and other engagement metrics accurately. Spacing out your email sends allows for better tracking and analysis of campaign performance.

To ensure a successful email campaign, it's generally recommended to follow these best practices:

- Spread out email sends: Instead of sending a large batch of emails all at once, consider spreading them out over a period of time. This helps distribute the load on your email server and maintains a steady sending pace.

- Segment your recipient list: Divide your recipient list into smaller segments based on specific criteria such as demographics, interests, or engagement levels. This allows you to send targeted and personalized emails to each segment, resulting in higher engagement and better deliverability.

- Monitor sending metrics: Keep a close eye on email metrics such as open rates, click-through rates, bounce rates, and unsubscribe rates. By monitoring these metrics, you can assess the effectiveness of your campaigns and make data-driven decisions for future email sends.

- Follow email marketing best practices: Adhere to established email marketing guidelines, including obtaining explicit consent from recipients, providing easy unsubscribe options, and delivering relevant and valuable content. By following best practices, you can build trust with your audience and maintain a positive sender reputation.

By being mindful of the volume and timing of your email sends, you can enhance deliverability, engagement, and overall success of your email campaigns.